SIZE=10000, FPS=22.5 on my PC. Isn't that enough?
In the Pre - DO NOT use DRAWSPRITE commands for such a huge number of sprites. Use the polyvector / plynewgroup method instead. Texture changing and glDrawXX calls are so expensive on these gadgets.
I have Wumbo's Adventure (15x10 tiles, 32x32 pixles) with a sprite layer for the enemies and a background layer for the hearts running at 60 FPS on the Pre2 with OS 2.x.