Watching your post since I just bought this same tank (it's still cycling) and my planned list looks very similar. My question is can I add a clam if a I have a pistol shrimp/goby pair or will the shrimp bother the clam?
I don't think a pistol shrimp would. While mine definitely buries the occasional coral on the sand bed or will move loose frags, it doesn't pick at anything. Now my cleaner shrimp on the other hand definitely picks at corals, feather dusters and my Coco worm. I would not feel safe putting a clam in the tank with him.