Are you sure those wheels are *only* 1700 grams?

I'd say a new set of wheels could save you 300grams and still have Al rims (more than a frame upgrade) and you can pick good hubs, rims and spokes to your own taste for that price.

I wouldn't go BHS hubs -get some local manf'd hubs- but the BHS wide rim is pretty good and should be stiff enough to allow you to use less spokes.