With your weight of 140lbs, and you say you won't be jumping curbs or anything, I wouldn't get more than 28 rear 24 front. You could easily go to 24 rear and 20 front. With kinlin xr-270 rims and good spokes you would have a plenty strong wheel set.

I would avoid the dura ace hubs. It's an unneeded cost and the loose ball bearings can be an unwanted hassle for somebody with no experience. Formula rear hub is fine. If your goal is to cut weight in the front, hub is the least important part (closest to the center of rotation), and will cost a lot more money.
standard road hub - $17 - 146g
white industries bling - $100 - 94g
American Classic lightlightlight - $124 - 58g