For starters what do you have now for inhabitants?
Everything looks fine, but I would add it slow if just starting (like half of what you listed) and then eventually double it.
Everything I have seen says as many as 1 snail and 1 hermit/gal
so you have plenty of room.
I agree with tripper on the peppermint. 1-3 as they are good for cleanup and would proven any future aiptasia problems, but don't count on seeing them much.
Otherwise emerald crabs(1-3), cleaner shrimp, and camel back shrimp are all nice choices. Starfish are always nice too. If you have a sand bed the sand sifting stars are suppose to be beneficial.
Getting a variety of snails instead of all one kind would be my only other suggestion.
As always slow acclimation with all inverts.