I concur that you should go West first, if for one reason - there's a culture shock coming East (where I'm from), people on this side of the country aren't very relaxed...it's just, different (it's from the long winters and congested commutes).

That being said, if you do come up to New England, I can recommend US-7, from CT through MA and VT as an idyllic ride. If you want a little more excitement, Boston is easily accessible via the MBTA ('T'). I'd suggest stopping at Framingham off of the turnpike and riding the rail into the city if you choose to go. It will be cheaper than trying to park in the city. www.mbta.com

Try to avoid the week the Brimfield Flea Market is on (May, July, Sept.) and I also recommend avoiding I-84 in CT. Try the Meritt Parkway instead (no commercial vehicles).

As far as the money situation, you have to decide how much you want to see and do (i.e. museums, dining, entertainment, etc.) and how much you just want to relax. Pack a cooler, shop at a grocery store. Camp instead of hotel. Maybe take a couple of weeks and ~$750 and see what's left at the end of that period. Bring a (very good) friend. For the amount of mileage you want to do, it would be in your best interest to have someone share the mileage. You don't want to fall asleep going into the Eisenhower Tunnel on I-70 at 3am.

HTH