Today I was informed that we had a performance tester built in to our asset assembly kit. I couldn't help myself, here are nearly 300 spaceships all with rotating fans (not that you can see the rotation in an image).
I believe that the spawn amount is currently based on available screen space only. Once we have a good number of ships fully assembled, I'll ask our programer to add some controls to it so we can see how far we can really push it.