From NY I had once been on an excursion that ran up the east shore of the Hudson to Stuyvesant and then went up the ramp to the Boston Line, crossed the river to Selkirk and then went down the west shore back to Newark. They could alternatively do the cross over to the Boston ine from Albany, or go all the way to Hoffmans to get on the Selkirk Line. It was a very nice trip. I have lots of photos of the non-digitized kind sitting in a box somewhere.
The only problem is getting CSX to come on board with the trip, especially with a very congested river line. IIRC, Amtrak had a difficult time in getting CSX to allow them to run the Sunday trip because of the highline being under work curfew, and the B&O was going to be congested.
I would like to see a trip to Bingo from Albany, however, I don't believe there aren't any decent connections to get down there without having to run a locomotive around the consist. I'm not sure if there's much more rare mileage opportunity out of Albany as Amtrak pretty much runs in all directions out of there.
Here are my suggestions for next year, kinda wished Amtrak asked this in the survey! My suggestions are trips out of Harrisburg, which has a lot of potential, and not far from the Philly base:
NS Buffalo Line to Sunbury, and then NS D&H to Steamtown and turn on Steamtown Wye. If there's enough time, allow people to visit Steamtown as part of the $129 fare.
NS Buffalo Line to either Williamsport (Turn on wye at Antlers Industrial Track), or continue to Keating and turn on the Corman Connection if Willimasport would make the trip too short.
NS Lurgan Branch to Hagerstown, MD and Return.