OK, I went through only part of the 25 pages of bug reports and issues, so some of this may be duplicates, but here is my list of bugs and serious issues:
Bugs:
I just tried to finish a game through a quest victory. After assembling all the pieces of the forge, I returned to the fortress thing that started the quest, and nothing happened. If I was supposed to go somewhere else, there was no hint of it. I can provide you a save of that if you like.
Crashes during tactical battles, of course
Sometimes, a resource with a structure on it will fall into your zone of control but will not actually contribute to your empire. This seems to happen mostly when you envelop another city and the resource is much closer to another city than yours (but it is still in your territory and built upon). Clicking on the resource claims it is producing, but does not say it is linked to a city, nor does it show up in any city's production summary.
Some quest locations do not seem to work. In particular, I found a dungeon (quest level 3) that my champions and sovereign could not access (I had the tech, just nothing happened when I moved to it). I was also once unable to complete the quest from the dungeon with deep claw marks on the wall because the destination similarly did nothing when my champions/sovereign arrived.
Suggestions/Issues
(may or may not be bugs)
Please make an option to make combat animations faster
Allow building of mines/farms/etc on tiles with units on them.
Sometimes when I try to build a city it claims the city must be built on an empty tile, but the tile seems empty. I assume there is an invisible quest/notable location there that is blocking me. I shouldn't be blocked by things I cannot see.
I always seem to have a lot of food (granted, I seem to have a lot of cities), but it seems to devalue food as a resource. I rarely build irrigation for instance because I always seem to have 20+ extra food, even expanding my cities as fast as I can (even with +1 prestiege from my sovereign and a +1 prestiege champion and prestiege generating buildings). Maybe this is just from how I play.
Auto-resolve combat does not seem to work all that well when I have ranged units and the enemy does not. Battles where the enemy should be killed long before they can get near enough to damage me (we're talking should be dead in the first round) sometimes result in my melee and even archers taking damage.
The random rolls for magic damage in the game seem...wrong. My spells say they can do up hundreds of damage (if I have a lot of elemental shards and high level casters), but in practice, they rarely seem to do more than 10 and never more than 20, even against enemies with very low defense. Enemy sovereign spells seem to be able to do 60+ damage all the time however.
I wish there were a magic resist stat in the game because I worry about sovereign spells (and moster specials) a lot more than regular attacks most of the time. If regular defense also works against magic, perhaps the UI could be more explicit about that.
Most champions are male, which makes it advantageous to pick a female sovereign (more potential mates).
Notable locations are not always easy to see on the cloth map. Especially Scroll Cashes near mountains. Perhaps their colour could be changed so it is not so close to the mountains/hills colour on the map?
Health and movement increasing techs in the Warfare research tree do not seem to do anything.
The Vigilant Watcher that all the computer soverigns seem to get that does 10 damage to all units (and that I have seen them cast twice per fight) seems like a crutch for the computer. Do they really need such an overpowered unit? Alternatively, where can I get one?
Prestiege increasing champions do not seem to function.
