The following is a copy of a good comprehensive roundup by Transitive which was buried in the middle of an older post that didn't get much recognition. I think it is worthwhile repeating. (Note: again, I reordered the ships to match the above order: TEC>Advent>Vasari with Battleships>Carriers>Colonizer>Utility>Seige.
Gauss Gun - pretty good ability, great damage and rate of fire balanced by high antimatter usage
Flak Burst - extremely good ability, best anti-squadron tool available to TEC. especially brutal against Advent squadrons which have more ships but lower hull per ship.
Adaptive Shield - the ability itself is very strong but getting enemies to fire at your Kol in preference to other ships is difficult. this doesn't work as well for "tanking" purposes as it should. I'd like to see some kind "draw their fire" effect added to this similar to the Animosity ability of a Radiance.
Finest Hour - fantastic. i love this ability, its perfectly balanced, fun, flavorful, powerful. great all around
Missile Battery - sort of like a portable LRM on the spot. not a terrible ability but kinda bland.
Embargo - great ability, the only thing really worthwhile about the Sova
Heavy Fighters - boring and weak. this is the last ability taken whenever i build a Sova.
Rapid Manufacturing - this ability is awful, it basically does nothing unless you've got a Sova parked at one of your manufacturing bases. generally speaking this is stupid, especially since Embargo encourages you to go on offense with the Sova. this ability should be scrapped and replaced with something completely different.
Colonize - not as good as the Jarrasul or Mothership colonize abilities. could use a small buff.
Ion Bolt - very good disruption ability, the best ability on the Akkan
Targetting Uplink - hard to judge whether or not this actually does anything that matters. the range boost seems unimportant. the hit% boost is alternately extremely bad or extremely good, depending on circumstances. this makes this ability kinda inconsistent. i don't like this one very much.
Armistice - meh. this doesn't seem to do much in terms of helping you actually win. i'm not that impressed by abilities that make it harder to lose.
Shield Restore - I personally dislike this, though some players swear by it. The Dunov can't target itself so it just ends up becoming the target instead of whatever you were trying to save. on the other hand some see this is a great way to save a more important ship (a level 6 Marza, for example) from dying to focus fire. in any case the ability is good enough and doesn't need anything changed.
EMP Charge - a fantastic ability. i love this one. against ships with full shields this has a gigantic damage potential. this is also one of the best antimatter drains in the whole game.
Magnetize Hull - another very good ability. pretty good at destroying squadrons (but not as good as Flak Burst) but its also a very nice interrupt/disable sort of ability to use against enemy cap ships.
Flux Field - this is a great ability in every way. its fun and flavorful and you can do some really powerful things if you combine this with the right ships. amazing with a Kol, you can just spam Gauss cannon shots and Flak Bursts and kill everything near you.
Radiation Bomb - an average quality direct damage ability. nothing special, but not terrible either.
Raze Planet - extremely good bombing ability. one of my favorite powers in the game.
Incendiary Rounds - an average quality passive ability. modest damage boost but convenient in that you don't need any antimatter to get the extra damage so its good if you're jumping around alot.
Missile Barrage - controversial to say the least. personally i think its grossly overpowered and needs a big nerf. others will disagree with me on this point though. in any case, its EXTREMELY POWERFUL.
Ignite Antimatter - extremely strong ability. best "abilities disabled" power in the game. makes the Radiance a real beast against enemy cap ships.
Animosity - pretty meh except against AI. the issue is that this ability doesn't in its own right grant added durability. you can get Animosity and the Armor passive and then stack it with a healing power (Perserverance or Extend Shields+Shield Restore) to soak up alot of damage, but then if you already had that level of healing power Animosity is kinda redundant.
Energy Absorbing Armor - pretty good passive. even just absorbing some AoE or stray shots will keep the Radiance with enough AM to cast Ignite very frequently. the added durability is just a bonus.
Cleansing Brilliance - an above average "super beam" weapon. a nasty shot to the junk of an enemy capship or starbase and it also causes some bonus damage to anything in the way. its also really cool and flavorful and fun to use. i like this one. still works well with Malice by the way, just not the "instagib entire fleet" level that it used to have.
TK Push - a very strong anti-squadron ability. really helps maintain squadron dominance, fantastic support. also makes it very difficult for your cap ships to get strafed by a big column of bombers. good stuff all around here, sort of combines the best of both Flak Burst (the AoE damage) and Jam Weapons (preventing instakill bomber strafing runs).
Adept Anima Pilots - very bland and weak passive ability, like Heavy Fighters on the Sova. last thing i put points in.
Energy Amplification Aura - this is ridiculously strong. makes all your ships do much more damage but is particularly brutal with Illuminators and Destras.
Anima Tempest - this is actually extremely powerful. can be used to give some nice burst damage on your strafing runs but is even more useful as a way to nearly instantly regenerate the ships in squadrons that have taken alot of damage.
Colonize - best colonize ability in the game. the only colonize power i ever put more than 1 skill point in. fantastic.
Malice - i like this ability alot. i usually get it later on though since its not actually powerful until you've got a pretty big fleet backing it up. can pump out serious pain if you've got something good to use with it like a bunch of Illuminators or Destras.
Shield Restore - the best ability on the Mothership and the real heart and soul of every Advent "battleball" fleet. this is one of the most powerful abilities in the game. must have material.
Ressurection - the mothership itself is probably the first ship your enemy will try to kill, therefore making this ability almost useless. i'd like to see this changed to a Reincarnate style ability that allows the Mothership itself to come back in some way.
Vertigo - pretty good debuff. could use a slightly bigger radius and its a shame it doesn't affect cap ships or starbases, but its generally very good at containing the damage output of LRFs.
Vengeance - kind of a cute combo with Animosity but ultimately this isn't that great. maybe i'm wrong and somebody has gotten REALLY good at using this and can do savage damage with it. myself, i'm not so great with it so i usually skip it and get Vertigo which is easier for me to manage.
Concentration Aura - very strong ability. if you've stocked up on Aeria Drone Hosts then you really owe it to yourself to go get a Rapture for Concentration. big damage boost.
Dominate - this is pretty good. basically one shot kills any enemy frigate, taking it over for your own fleet is just gravy. note that you lose any researched special abilities so there's no point in using this on support cruisers. best targets tend to be Heavy Cruisers and Carriers. its also damn cool. this is how Professor X would fight if he had a space ship.
Guidance - helps the Mothership spam more Restore Shields. that pretty much the only thing i ever use this for. i don't actually like this ability very much.
Reverie - this is an average crowd control ability. its really a whole lot like Phase Out Hull. nothing wrong with this ability, its useful, just not tide turning all by itself.
Reveal - i never get this ability. there's nothing wrong with scouts.
Incite Hysteria - this kinda sucks actually. compared to Drain Planet its pathetic, doesn't stack up.
Power Surge - a very strong ability that provides a great boost to both offense and defense. great synergy with Disruptive Strikes as well.
Jam Weapons - an average quality anti-strikecraft ability. i typically don't get this until later on because its really only important when very large quantities of squadrons are involved. still, its good at what it does.
Disruptive Strikes - a very good passive ability that makes the Kortul absolutely brutal against other cap ships and support cruisers.
Volatile Nanites - a very good debuff that can result in some serious carnage if you manage to set off a good chain reaction with it. works especially well with other AoE damage abilities such as Charged Missiles. i like this one.
Repair Cloud - fantastic ability, the main reason I ever get a Skiranta. this is the only ability in the game that can repair squadrons directly. this adds to fleet durability by a huge amount and also helps with squadron superiority.
Scramble Bombers - pretty mediocre. uses too much antimatter. you get more benefit by just bringing an extra Lasurak along with you, why waste your antimatter and skill points on this?
Microphasing Aura - very good squadron support ability. this is particularly great for establishing air superiority, this makes it very easy for your fighters to shoot down enemy squads and very hard for enemy squads to shoot yours down.
Replicate Forces - pretty nice ability. its not particularly powerful but its a nice boost, especially if you've got something good to clone like Skarovas Enforcers. its also fun and flavorful. i like this one.
Colonize - pretty good bonus ability (20% faster structure build rate). the bonus is particularly nice when the first building you build is a Repair Bay or Frigate Factory because there's a fight still going on in the grav well.
Gravity Charge - very good ability for cornering damaged ships with as they try to escape. not very many good uses besides that though, but it makes it very scary to go toe to toe with a Jarrasul since you probably can't get out alive if it goes badly.
Nano-Dissasembler - probably the best single target direct damage ability in the game. absolutely lethal and it scales well with your fleet size due to armor debuff. great ability.
Drain Planet - the best planet bombing ability in the game. indispensable for Vasari on offense, kills planets very fast.
Phase Out Hull - a pretty good crowd control type ability. also interrupts channeling and phase jumps, and can even be used defensively on your own ships. its pretty versatile. not extremely strong though, just versatile and useful.
Subversion - pretty awful. this has an extremely minor effect unless you can somehow manage to get your Antorak into a major production facility of your opponent and then somehow not get killed. the risk:reward ratio on this seems off. compare to similar ability Embargo and it really comes up short.
Distort Gravity - uses too much antimatter. it would be useful but it seems like after just a couple of jumps you can't even power it up anymore. for an ability thats supposed to help get behind enemy lines this can't be used often enough to actually accomplish that task.
Stabilize Phase Space - very impressive ability. lets you fly in reinforcements from anywhere and totally blindside an enemy. would be EVEN BETTER if Distort Gravity worked better and you could get further behind enemy lines.
Phase Missile Swarm - above average AoE damage ability. kinda boring but functional.
Siege Platform - a very good planet bombing ability. lets you keep hammering the planet even if your Vulkoras has to do something else for a couple of minutes.
Assault Specialization - a very good passive ability that makes the Vulkoras a champion at destroying orbital structures and blasting planets. the combination of this with Siege Platform makes the Vulkoras the fastest planet killer in the game.
Disintegration - an average quality "super beam" weapon. not quite as good as Cleansing Brilliance, but still a big kick in the teeth to an enemy cap ship or Starbase. its pretty good overall but its nothing special.