It's not quite the NEC, but I'd be
highly interested in either BBRR all the way through VA (e.g. the ex-C&O route) [1] or the ex-N&W through West Virginia. If you go to either Staples Mill or Newport News, turning should be a non-issue. The ex-C&O James River Line would also be of interest to me (and probably to a few folks I know) as well as the ex-Pennsylvania line from Cape Charles to Philly (definitely a wye at Cape Charles [2]), as would the Shenendoah line (Hagerstown to Roanoke, I believe [3][4])
Also of interest would be the ex-B&O Washington to New Jersey and/or the non-Metropolitan Branch B&O line. The ex-B&O would probably terminate in Hoboken, and I'd be honestly
shocked if you couldn't turn a train around there
somehow.
[1] They're not doing it this year, but one year when W&M plays UVA? Bit of a rivalry there, quite literally going back to the 19th century. Actually, scheduling "game trains" for the CAA schools wouldn't be hard if you can get the access...most of the schools are either along the NEC, the Virginia lines, or the Downeaster route. The only exceptions are Stony Brook (on Long Island; cue issues with some of the curves) and JMU (Harrisonburg, VA...no clue if that's even on a line.)
[2]
https://www.google.com/maps/place/Cape+Charles,+VA+23310/@37.2655447,-76.0134293,15z/data=!4m2!3m1!1s0x89ba5c609acedfa3:0x52caf608b4c59f27
[3] The line crosses the ex-B&O mainline/Capitol Limited route at Duffields, so in theory you could base this out of WAS...and in another year or so, ROA will have an Amtrak station as well.
[4] The other option here would be the NS/Crescent line out of WAS followed by the NS branch to Front Royal. In general, I'm
trying to keep you on a single Class I for a given trip.