Warrior is "eh..so - so". You get first strike (When attacking, not defending) menaing all your ships shoot first, then whatevfer is left alive, shoots back. Just on the first turn.

Hive = cheap factories. So they buy faster and build faster. Hard numbers I dont got, but they are cheap.

Breeder - I think its a 8x multiplier to population growth (per planet) when you are at 100% approval.

Isolationist - Enemy vessels move at max of3 spaces per turn regardless of speed when they are in your realm of influence. And you can colonize barren planets.

Diplomat - makes your trades better for basically everything. You get better deals on everything. There arent really any hard numbers, but tech trading is easier, selling or buying ships and planets from AI's is easier, and you can talk with the AI more frequently, I think every 4 turns or so, as opposed to 12 turns. Basically it makes you smart enough, good enough, and dawgonnit, people like you.

Manupulator - You can get AI's to attack each other more easily, not real numbers to give.

Super Spy - start with counter espionage and 1 spy. Is what it is.

Super Organizer - AI's with similar ethical alignments will sometimes come to your aid when you are attacked.

Super Annilator - Spore ships. They rock. You "spore" a world, it turns toxic and becomes yours...with small colonists already there and infrastructure intact.

Super Dominator - you get little ships when you declare war on people, more ships depending on current size of your military, but not really all that great.

Super Ghey Iconian Ability - colonize aquatic and some other hostile environment, maybe radioactive? I dont really care to look at it to remember.

Super Trader - start with all the trade techs ( trade, advanced trade, master trade ) and I think either a bonus to trade or extra trade routes, I don't remember

I would play them ALL, to see which is "best" for you. My guess would be you like Hive, Breeder, or Diplomat the best.

Hive: Factories (buildings that give x industry, but not buildings that give x% industry) cost 25% of the "real"/base cost to build. This also applies to rush buying if you put them in the build queue first; per the rush buy formula of base cost^1.1 (and then truncated) * 6.

Breeder: 8x bonus to pop growth at 100%, as opposed to the normal 2x. A better way to think of it is just to factor a 4x into the complete formula-that's how I think of it, anyway.

Note on Diplomat: 4 turns versus 8 turns, IIRC, not 4 turns versus 12 turns (unless this has changed in TA, which I'm still a little rusty on, but I doubt).

Just some clarifications-Piznit got the vast majority of it correct.

If anyone knows, I'd be interested to hear how much Super Manipulator saves on buying wars. It's a lot more useful in TA with the new Drath tech tree & war profit, but I've not been able to figure out how much value for money I get (it "feels" like it works, since everyone's too busy to attack me and I'm loaded...) Also, if anyone knows how the number of Super Dominator Corvettes per war is determined I'd be interested, I've played a couple of games where Drengin have started several wars in quick succession (or I bribed all the others into attacking them) and the numbers have been unending. It's not the best ability but it gives great "evil empire" feel to any race.

In DA, my favourites are Diplomat and Isolationist, I also like Warrior because I get more experienced ships due to their longer lifespan but can survive without it. Organizer's my least favourite because it's only helpful once you're attacked, but less reliable than Isolationist as a defensive ability.