That's what the winter Polar Express trains are. 25 minutes each way in the dark, barely up the route, but they sell pretty well.
The summer runs were never really intended to be excursion in nature, they were meant to be tourist/transportation - bringing people to otherwise hard to reach places in the Adirondacks to explore. Some of the stops were campgrounds, where people could disembark, tent up, and come back down the next day. The great thing about it as originally planned was that they reactivated all the original D&H stops along the line, rebuilding several to commuter rail quality (Hadley, Thurman, and North Creek itself).
If they want to do adult excursions they need to shorten the North Creek layover to at most 2 hours. Enough for a meal, look around a bit, then back on the train. I'd probably take a trip like this 2-3 times a summer. To do this they'd have to either move their initial departure to 11AM, or the return departure to 2:40PM. The problem with the latter is it would find itself stepping on the NY-bound Adirondack's arrival.
I guess if they want kid-friendly excursions, they need to go up to Hadley, makes a 10 minute station stop, then back - total trip is just within 2 hours. Which would suck, because it would effectively abandon the North Creek part of the Saratoga and North Creek. That said, they *could* run a schedule like that with broad appeal on special racing days, such as Travers' day. It provides a reason to get up to Saratoga early (before the traffic), a good alternative to the first few races, and brings people back with plenty of time (and bankroll that would have been lost anyway) for the featured race.