The only other fish I'd think of if I thin out the tank is a falco hawk. But that is if I get rid of the algae blenny. I read afterwards that they can get mean when they grow? He's so fat now it looks like he'll explode and he still eats!
the Hector goby swims around more than the randall's so I don't think I'll have an issue with those 2. The blenny though staked his claim on top of the next rock over from the clowns and their anemone. It's good he blends into the rock or there may be more trouble than there is now. I don't know what will happen when he grows though.