Sono-k is usually better than the Pyro-k.
I think Pyro levels ought to count for psicrystals.
While I agree on both counts, I want a good-natured pyromaniac for my group's skillmonkey, which is one reason I took swordsage; Desert Wind is good for that.
The pyro is good for both fire and for making touch attacks with reach.
It's a shame that whips suck so much, though (albeit less so with the flame lash).