I like croaking and sparkling gouramis. They're not as aggressive as the larger ones. Even dwarf gouramis can act nasty. Honeys are on the peaceful side, but if you want something uncommon go for the croakers. They make noise.
I have a dwarf powder blue that's been fine for a couple years, even with the platy and gbr. Once in a while he starts to get a little 'touchy', but never hurts anything and everybody is faster anyway. Lately the male platy pretty much stays with him, apparently trying to mate. I used to have a sword in there and it was the platty that picked on him incessantly, so I moved him up with the betta(the sword).
This is a quality pet store gourami and not one from petsmart. He's been a great fish. When I come up to the tank he goes bonkers swimming along the top back and forth, with his dorsal poking out of the water.