FWIW, I recently brewed a beer with a pound of extra dark crystal...even though it finished at 1.002, it's still sweet up front.
I'd cut the muchich back to a half pound, and swap the c60 out for a half pound of dark or extra dark crystal.
The half pound of dark crystal will give you a somewhat equivalent amount of flavor as the pound of c60, but with less of the sweetness/body issues. Yes, it's not the exact same flavor as c60, but I doubt it would be noticeable.