By just "3DS XL" I'll assume you mean O3DS XL. That, compounded with sysNAND 10.5 leaves you in a tough spot in terms of GBA/32x/PS1. You can't run dynarec, which is how those emulators get better speeds (requires kernel access, which isn't available on "vanilla" 10.5), and you're also on O3DS, which is a slow device, not to mention you can't downgrade without a hardmod (yet), so GBA can't be accelerated with AGB_FIRM.
There's not really a lot you can do in your current situation, no, not without downgrading, and even if you do, GBA/32x/PS1 will all continue to run poorly (as in, not full speed) due to it being O3DS (except if you run GBA on AGB_FIRM).
