If you save ships from one race as a quick formation, you can change race afterwards and load in again the ships you just saved from the other race. This way you can field ships from all 4 races at the same time, if you want to. I see little utility in this, except to exploit it, by using different racial modules, to try and get higher scores (something I have not done, since I would consider it cheating). It might just give the little edge needed to get to the top of the high score list.