I would go with turbos,mexican turbos and trochus snails for the glass and rocks.Nassarius and ceriths snails,2 fighting conchs and a few atlantic spotted cucumbers for the sandbed.
You should add a clean up crew slowly as you see a need for each type.I do not advise getting a large package....a clean up crew is something that I add to as I see a need.Crabs are NOT necessary...but if you do add crabs,remember that all crabs are opportunistic.Of hermits,scarlets seem to be the most peaceful...but even they can be problematic.Even when extra shells are available,they can sometimes still kill a snail for his shell.
In my reef I removed all hermits except one electric blue.In my semi-aggressive tank I do use hermits.
Shrimps like skunk cleaners can be good scavengers,and also will usually clean your fish.
Serpent stars can also be good scavengers,avoid green ones as they are predators.