I would in a heartbeat. When I lived in Philadelphia I did some great rides west of Wilmington near Chadd's Ford and in and around Brandywine Creek. There used to be an organized Three States ride where the route would go around the intersection of Pennsylvania, Delaware and Maryland. It's beautiful country but it's not flat; pleasantly rolling, no really steep hills. Go to Maps.Google.com and switch between map and satellite and terrain. Lots of woods and farmland.

There are lots of routes that will keep you off the congested arterial roads but it will require lots of turns. I used to make up my own cue sheets with turns, road names and distances to the nearest tenth plus I carried a photocopied map of the area.

Two clubs in the area: Brandywine Bicycle Club and Bicycle Club of Philadelphia.