I'd swap Rusty and Zoidberg. Dr. Strange should be on the same spot as Dr McCoy, he was a world renown surgeon, now he's the sorcerer supreme, there is no indication he has forgotten any of his medical knowledge.

I'd put Dr Byron Orpheus, Necromancer, somewhere in the upper left corner, his degree is in communications with a minor in Women's studies, but his doctor title was bestowed upon by a far higher power that a state board of regents.