I’d only see them doing it if they had some type of equipment stationed up there and ran from both Conway and another location further west. At that point though, you’re stretching yourself quite thin with the employee base and motive power and whatnot.
At this point, any expansion on the Mountain Division is a moot point. If they were to run to Whitefield regularly, (lets use the possibility of NHCR signing them the lease from Hazens) to make that a day trip, they would have to upgrade speeds significantly. I believe they keep the current speeds at a max of 20 MPH to bypass FRA regulations pertaining to having a dedicated dispatcher, track warrants, etc... Additionally, most of that 85 LBS rail has to be beyond shot at this point, which new rail or even relay isn't in the budget for the railroad without state or federal assistance. Yes they could expand down the Conway branch, but keep in mind 99% of the ridership on Conway Scenic are not railfans. I think its safe to say the 1 hour or so round trip to Conway and back is more than enough for families. Conway already offers longer excursions if they are interested.
As for freight, both lines have been closed for 40+ years. As others have noted the millions it would cost to bump speeds up to 10 MPH wouldn't be worth the less than 100 cars a year they might pull collectively from either line. Additionally when you start moving freight, that is a whole different ball game for a tourist railroad. It opens more hoops to jump through with the regulatory agencies, additional training employees have to go through etc... The general manager of Strausburg mentioned this in the "Roundhouse" podcast several years ago. Plus with todays 263K and 268K cars, that adds a lot more maintenance to the track than a tourist train. At the end of the day, yeah it would be nice to see some abandoned track reactivated. But is it feasible? Probably not. I think the potential customers Conway Scenic supposedly found, would get a better bang for their buck transloading on SLR or NHN.