Not that I've ever done it or played with it, but that would be my first attack angle too. The particles seems very controllable and flexible. Smoke are sprite based particles too and it seems to expand and contract nicely. The cool thing with sprites is you can assign any bitmap too them with different size particles, so it shouldn't be too hard to get it to look like a swarm once you've got the behaviour of the particles down.

Maybe some maya unlimited and particle type guy can chip in.