wingnuts are awsome in so many ways, good decision to keep them. as for rims i'd say mavic ma3; i've never been dissapointed by them, not pricey and they stand up if you have the wheels built well. you could probably get cheaper Alex rims but i find that they wear really fast (at least mine did) if you ride in bad weather conditions.

good luck with the seatpost. see what keith has to say about that issue.