Also keep in mind you can manually set it to low res, and playing in windowed mode significantly helped for me. The current price on Steam is incredible, and it's gonna be gone in ~12 hours from now.
Eventhough the New 3DS XL is more powerful, I still feel like the DS Lite was a more polished system. It's a real shame that it never got an XL variant keeping the GBA slot. You'd have to go on AliExpress and buy an ML shell to give a DS phat the unofficial "DS Lite" treatment, and that's the best we'll ever get I'm afraid.
@Jayro, I don't see whats so special about the DS ML, its just a DS lite in a phat shell. At least the phat model had louder speakers, whereas the lite has a much better screen.