The slot-2 Supercards and M3 Perfects contain 32 MB of RAM so you don't have to write them to NOR flash like you do with the EZ-Flash line. However, the Supercards suck for GBA games, and you're never going to be able to find an M3 Perfect anymore.
The best you can do is try to trim your 32 MB rom so it takes a few seconds less to load it to NOR. Also note that once you've written it once, it will boot up instantly until you decide to swap it out for another 32 MB game.