I'm curious why you would buy a LHT if you aren't going to haul stuff with it, as that is pretty much it's raison d'etre.
As for wheels, there's no point in going lightweight with that bike. Have your LBS build you some wheels with DT Swiss 350 hubs, good alloy rims (tubeless if that is your thing), and DT Swiss Competition spokes - 32h or 36h. Should be about $800 or $900 and will be bombproof.
Edit: I see your price limit is $600. Go with cheaper hubs (the Bitex hubs recommended above are fine) and some DT Swiss rims that are reasonable. Welded vs pinned rims make no difference. But really, I would ride the stock wheels until they had problems.