Where in NJ are you? I ride in Hunterdon and Warren Counties fairly often in the fall, spring and summer. Lots of great riding in those areas. Did the Black Bear Century for the second time this year.
For scenery and mostly quiet roads, riding from Port Jervis, NY, pretty close to Montague, NJ, through the Delaware Water Gap NRA and then continuing down the river makes for a very nice mini-tour. I did Port Jervis to Philadelphia last May. This is part of ACA's Atlantic Coast Route. There is camping on route just outside of Port Jervis, at Worthington State Forest near Delaware Water Gap, PA and at a couple of private campground south of there. Spring is a terrific time to go as there is very little traffic in DWG compared to summer. Another nice thing is that, for the most part, the hills are not that bad, although there are two nasty ones in the NRA. Not real long, but steep in places. Port Jervis to Worthington is about 35 miles, so you can ease into it. The camground at Worthington is right along the river. And south from Frenchtown, NJ you can take a nicely-surfaced trail as far south as Trenton.
Send me a PM if you would like more info and possibly some other ideas based on where you are in NJ.