I don't know your family dynamics, but both the Outback and Glory Days are good for lunch for families. They're both chains and the food is what you would expect from a chain. Both offer burgers, salads, etc., and have kids menus. I suggest you check the online menus for both and see which one appeals more to your family.
That said, the biggest difference is in proximity to the AT station. Glory Days is much more convenient since it's practically across the street from the AT and you could relax more during your meal knowing you wouldn't have to be concerned with traffic to get back to the station. Outback is further away and getting there from the AT station is a little more complicated, but not bad if you use local roads instead of I-95.
Locals miss the Polo Grill, too; it was there a long time.