Lighting would be a lot more manageable with the shallower depth too. Altho I don't think the intense lighting that most people go with is entirely necessary either. Corals don't get as much of their energy needs from their symbiotic algae as people think they do. Mostly just enough to cover their metabolic needs. They really need to be fed more than people assume.
With that floor space and a similar sized refugium, you could definitely support some dragonetts. They require supplemental feeding, but with that much space for copepods to reproduce, they could do very well. Very few reef tanks can supply enough food for for them. The only issue would be having a spawning pair with a shallow depth like that. They swim rapidly towards the surface during spawning and would easily be lost in such a shallow tank without a cover.
Man, I have a severe case of MTS and I don't even have a tank set up yet.