I think the look of your clouds is nice, but as for their movement I have a few sugguestions.

I would add some drag so that they slow down over time. Also, I'm not sure why they rotate around the charater. That doesn't look right to me. Lastly, they clouds seem to disperse by scaling down mostly, maybe it would be nice to see a little bit of a transparency fade.

Other than that, it looks good.:headbang: