It depends on weither you are pirate or empire.
Empires can play peaceful, however, giving the other AIs Starting tech level while you are on Prewarp, it is no wonder the AIs leave you in the dust. While the difference between prewarp and tech 1 are minimal in terms of warfare (only the shield generator makes an enormous difference), there is a huge difference in warp drive tech. Warp bubbles are next to useless, they are too slow and eat up too much energy, at best you can only visit the neighboring systems. It is not until you get Gainax where you will be able to effectively establish an interstellar empire, and the amount of RPs that Gainax requires are enormous. Tech 1 starts out with Gainax already researched so while you are struggling to get those initial warp techs, the AI will be colonizing the galaxy.
That warp drive advantage are the reason why pirates are so dangerous, even though they start off with no planets, cannot explore ruins, and have a hard time making any kind of income.
Overall, I feel that if you want to play peaceful, you should either push back the AI empires to Prewarp, or upgrade yourself to Tech 1. If you want replacement opposition, I highly recommend pirates.
Pirates, on the other hand, a peaceful pirate game is simply not possible. Empire AIs like to attack pirates, to even if you do play a pacifist game you will likely end up destroying a huge number of ships while trying to protect your stations. I have asked for improvements in pirate diplomacy to alleviate this so hopefully they might come down the road.
I ate the batter of the bulge at Hans' Haus of Luftwaffles