Surge was indeed correct, it was one of the factions that had a custom set of ship designs. Question, what's a good amount of factions to have on an immense sized map? I don't like having other factions starting to close to me where we meet before I have a chance to start building myself up.
I think this is a good question that have no real good answer... 
It completely depend on the map type (tight/loose cluster, scattered or spiral) how common stars, planets and how many habitable planets there are.
I would say that you need at least 15 AI opponent otherwise it will take ages for you to even meet someone, but 20-40 are probably more reasonable I think. More and I find that things just get too unpersonalized for me.