Well i suggest you try out diffrent multipliers in diffrent games. f.ex Tony Hawks runs best at around 3-5 multiplier, where FF7 runs best with Multiplier on 10. Some games can't even start with too high multiplier

Second, you need to play around with Frameskip, i recommend setting it to 1/2, but dont enable frameskip on all elements. Maybe only blits or something like that.

Consider getting a bios, scph1001.bin and scph7502.bin is the most recommended. I get better fps in some games using my own bios.

With these 3 things in mind you can make alot of games playable... at this point i can play: FF7, Tony Hawks 1-3, Abe's oddysee, Kula World, Diablo, Wipeout 2097, and few others. Also at this point i would say half the games i tested worked, and again half of those are playable, so thats around 1/4 that can be played, maybe more gl with it