dupontrob2000,
Last year I rode from ME to Richmond, VA, on the way to EOM and stopped in Richmond on the way back. I took I95 all the way down. It was a real PITA and nothing of particular interest to see since I wanted to get there in one day. The tolls were $21. I took the GW Bridge for free since they hit you double going northbound. No idea how much that is. The NJ TPK was over $9 for a lousy 110 miles. The Delaware Mem Bridge was $4. You get the idea. Rush hour within 50 miles of DC was a parking lot.
On the way back, I took I64 from Richmond over to I81 north.The riding was much better except for all the BSTs (big scary trucks) some construction and those revenue generating "Safety Corridors". I think there was a $1 toll at the bridge in Newburgh, NY, and that was it till I hit the NH and ME TPKs. I would do I81 again and cut across from there to DC.
If you do choose I95, I used to take Delaware 13 at the end of the NJ TPK to 301 in to Annapolis. It was a nice ride and not too much traffic. That was quite a few years ago, however.
DC is a fascinating city, just not sure it would be a destination for me on a cycle. Have a good trip.