Finding AI opponents / good mods

[Suicide Junkie]

Pirates & Nomads is a nifty mod for playing the underdog. When you play as a pirate, every battle is critical, and you cannot afford to lose ships.
Your major source of funding will be scrapped ships, and possibly slave labour from captured transports .
When you're a Pirate, you'll find yourself constantly struggling to balance a budget, defend your holdings with a small navy, and using every one of your sneaky, underhanded human tricks just trying to survive in a hostile universe .

Just be sure to follow these few instructions on how to create a truly Piratey race.
- select the advanced trait of "pirate" only. Adding "normal" or "nomad" will ruin the pirate atmosphere and make the game easy.
- don't wimp out and take a no-maintenance race
- set your reproduction and environmental resistance to minimum.
- (more optional) set trade and physical strength to minimum.

[Nitram Draw]

Dev mod is also excellent.There are a lot of new things in it. Latest Version is 1.31 I think. Only two new races but lots of new ship/components.