Instead of buying another $600 bike you could but a Surly Troll fork on your 3900 or similar solid fork and spend the rest on front rack/panniers and handlebar ends/grips.

The Trek 7.2 can work but so can MANY other bikes for $600+ If you're riding mostly on the road consider a drop bar road touring bike from BikesDirect and spend $150 or so for a bike shop to go over it. It's unfortunate that straight bars are the default set-up for entry level bikes. It's really not an optimum position for road riding.

http://bikesdirect.com/products/windsor/tourist.htm