I don't think buffaloheads are that bad of an option, but their small size worries me, since that could lead to their getting eaten, then again I've also seem some pretty small lamps kept with fronts for years with no problems
try and stay away from the peacocks, i used to have the peacocks in with the fronts and the peacocks keep on biting the fins of the fronts and now the trailers on the fronts are all short and damage and it will take awhile for them to grow back out. that's just my experience.