I wouldn't recommend blue leg hermits with snails, because they are known (I can personally atest to this) to kill the snails for their shells. Might want to just try an emerald crab, or some shrimp, and different varieties of snails (cerith, nassarius, margarita, turbo, etc). Good luck with whatever you do. Scarlet reef hermits are supposed to be much more peaceful in temperment, then again, hermit crabs in general can be mean? Am I alone in this thought or no?
(P.S. THen again, blue legs might work, because I have a complete haywire invert cleanup crew issues right now, the peaceful ones are becoming super aggressive, and the known "culprits" are excellent citizens, Go figure)