Okay, haven't been playing for too long, and don't know everything, so I won't answer everything. I'm also a TEC player, so I'm pretty sure about their stuff but not the other races'

A.) For TEC (and I think advent) there is a researchable cruiser costing 2000 credits and somewhere around 350 metal and 200 crystal (or maybe the other way around). The TEC one at least has no shields, and only around 1250 health, making it very weak (it also has no weapons). The TEC one takes up 10 fleet supply. For Vasari, the colonizer ship can build starbases (with research). Then, there is the ability of the cruiser that can make a starbase. For TEC and Advent, it costs 1000 credits and I dont know the metal and crystal. The vasari one costs 3000 credits, along with anywhere between 200 and 400 metal and crystal. The cruiser or frigate turns into the starbase, returning your 10 points.

B.) No limit on building the cruisers, only fleet supply limits it. One starbase per grav well. 3 per star grav well.

C.) Upgrades are listed in the area in the bottom right hand corner (whatever it's called). There are weapon upgrades (2 for tec and advent, 3 for vasari), shield and hull upgrades (3 for each? maybe), hangar upgrades (3 again i think), and then special upgrades depending on the race. You just click on a button to the upgrade. Each one costs 1800 credits and some more metal and crystal. But if there is a third one, it costs 2700 credits and some more m/c.

C1/2) 8 upgrades

D) best ask others for this.

Hope that helps.

a: 10 fleet for tha TEC and Advent construction cruiser, Vasari's comes from colony frigate. Once you turn the ship into a starbase it no longer uses supply howerver.

B. 1 starbase per side per well. 4 starbases per side per star well.

C. Its like planets, click on the starbase and you are presented with options. Each starbase has 8 Upgrade points, there are a lot of upgrades, you can choose 8. No going back. Some are tiered, so you need lvl 1 weapons upgrade to get lvl 2 weapons upgrade. The more unique upgades+ the tradeport upgrades, must be researched first. There are also global starbase defence and attack researches that make all your starbases better once researched by offering extra weapons banks or percentage defence increases; these are high lvl research though.

D. Lots of stuff, ill skim the highlights , all starbases have: weapons, defence, fighter bay, trade port and planetary government upgrades.

Weapons tier 1 is essential, as it gives the starbases their 'bite' in combat they are very poor without it.

Planetary government means that a colony cannot be destroyed (it could potentially be lost through culture still) while the starbase stands.

Advent upgrades:

culture generators

A max allegiance increase (very usefull more allegiance means more money and resources)

Mass disorientation (screws up all enemy ships in a large area, for a long time, allowing the starbase to annihilate attacking fleets.)

Meteor control (fun, but less usefull aoe damage at range or can be used to bombard the planet)

TEC:

Super repair Bay

Super frigate factory (very quick builds at higher levels)

Self destruct (BOOM!)

Vasari: (this is mobile in its grav well, no phase jumps)

Frontal deflector shields, (used for assaulting heavily upgraded starbases coz they cant flank it)

Debris vortex (sucks up debris and repairs hull)

Phase stabiliser node (temporarily creates a phase node.)

I think both TEC and Vasari can get colony pods witch offer a taxable population.

As with all of sins their are a lot of subtleties in the balance, so TEC can get more trade income, Vasari can get more guns on their starbase etc.

Hope some of that is of interest.

Which reminds me, if you try and jump out of a well with an enemy starbase in it, the jump looks red and you take significant damage and antimatter damage. So, even though you can fly past an SB, it will inflict big overall fleet damage to you, significantly weakening your attack force.