Hrm... A bit of a different take than these guys, but if your 60g is a 4' tank, I'd say you're likely to be able to house at least a single leopard just fine. They DO seem to do well on two feedings a day, just squeeze in a third feeding on weekends or when you get a chance. They will learn to avoid "reasonable" bits of aggression from other fish - most of the ones you listed aren't known for being particularly psycho, and so long as the angel doesn't fixate on the wrasse that shouldn't be a problem either.