Doubt I'll be very helpful since I had to Google Catskills to see where in NY you are but I'll at least give you a bump.
We are right off I81 and when we go Northeast, we go I78 to I287 and up. Looks like you could come South that way to Harrisburg, PA and pick up I83 to Baltimore. Follow I695 (the Beltway) to the west and pick up I95. Try to time your travel in Balto/Wash between 9A and 3P and you'll be OK. I95 runs with I495, the Washington Beltway. Follow I495 to MD5 and Pt Lookout.
Taking I81 wouldn't help avoid much traffic since you can't avoid the Balto/Wash corridor and still visit Pt Lookout which, by the way, will be worth the ride. Hope this helps.
2016 F-250 Gas
2015 Rockwood 2608WS