If you do really want flat rides, you could explore rail trails.I have a couple of suggestions, but they are not necessarily convenient for you.

Rail trails tend to have very gentle slopes...

There is one in the Berkshires that is great, and blacktop the whole way. It is about 11.5 miles long, so 23 miles round trip. It is called the Ashuwillticook trail. http://www.mass.gov/dcr/parks/western/asrt.htm

Also, near Jim Thorpe PA is a wonderful trail, but it is gravel surface which may be an issue in case you run narrow tires. It runs 26 miles, so 53 miles round trip. It is the Lehigh Goge Trail. http://www.dcnr.state.pa.us/statepar...highgorge.aspx

There are others, but those are two that I have ridden in the region.

The scenery is better on the Lehigh Gorge, but the surface is better on the Ashuwillticook.

To search various areas.... http://www.traillink.com/TL_Active_P...ch/default.asp