Well, since dosbox is basically a 386 emulator, I don't think anything would be really usable (comfortably) on it.
I believe dosbox primarily exists to run old dos games, and most of those would be just unplayable even on a 100MHz 060 with lots of RAM..
It's also written to be easily portable and that usually means sacrificing some performance.
I doubt it can outrun good old PC-Task unless it had a well written JIT. Which on 68k Amiga has to be written from a scratch, lots and lots of asm coding
On my old 400MHz ARM Symbian Nokia dosbox can't really handle anything and it even has JIT for arm in it.
So.. yeah.. what's the point? Of course if the author wishes so.. it's his time after all
And there's always the experience that comes with it.