I'm also not a fan of any crabs in a reef tank. I have about 3 hermits left in the 155, removed all the others and those that are left just haven't been caught yet. The kill snails for the sheer fun if it, and knock stuff over. I will never keep hermits in any of my tanks again. The only crab I like is my Porcelain Anemone Crab. The Pom Pom is ok, but he's in the refugium.
The berghias are awesome aiptasia eaters, but it is the only thing they eat. There was recently a group buy for them on MR back in January and I been trying to get zone from someone that no longer needs them, but haven't had much luck. You could see if you have better luck, remember, a lot of them don't like me because I mod here, lol
Stick with snails and shrimp for your CUC. Add in thirds so they do t starve in the beginning.