There seems to be a misconception: I'm not going WHM/BRD, I'm going BRD/WHM when I hit lv 30, and as matters stand (on account of the advice given here) WHM/THF from 18-30.
I think that BRD/WHM will have more to offer a party than WHM/BRD, since bards are (or at least seem) a lot more rare.