Clean up crew for a 55g

[Eouen]

Hi guys! I'm a bit new to large tanks, I have just set up a 55 gallon tank and was wondering what sort of clean up crew i should have or more so how much of what.
i have about 5 Astrea snails and 2 electric blue hermits already scurrying around. Along with 1 tiger bristle star and 2 sand shifter star fish who seem to like the glass more then the sand
I am wondering what else should i add to make this tank? I've been reading that most people are not a fan of hermits and other crabs so should i stay away from getting more of those?
Oh also where the best price for these guys would be too would help a lot!
Thank you for all your advice and help!