Yeah, feinting only allows the bluffer to attack w/o dex bonus to the bluffee.
But, I have no problem with allowing taunt or a similar effect as a bluff check. Bluff allows the character to make another act as desired for up to a round, which IMO would allow a taunt. I would put a modifier on it b/c the target is not going to want to give up any tactical advantage - probably 4 to 8 - as well as the feint modifiers LokiDR suggests.
I like the dilomacy houserule, but diplomacy doesn't seem like as good a fit to me, although I like the houserule fine. Bluff seems a better fit for the short-term rage/attack of a taunt. Diplomacy gives a long-term change to attitude.