Yeah, I think 15-20 is possible on new 3DS if threading is implemented correctly and maybe a cached JIT added. Would be a ton of work but it might just about be playable-ish on very lightweight titles. Not that I'd want to put that much work into...
It has come to my attention that the 3DS does not have a gamecube emulator. This is totally unacceptable!
Due to this, I have made my own. Running it as normal homebrew would make an already impossible port even slower so this one runs 100% bare...