Chena Hot Springs was chosen for the several activities in the area. They ranged from kids activities, to hiking, to hot spring soaks, to Aurora light watch. A really nice ice museum was worth the visit.
The hot springs run off-grid so there are amenities missing you would expect at other lodging venues, like individual room heaters. I've read where the staff will provide a portable for you if asked, but i found the rooms and covers plenty warm enough for autumn. A tour of the geothermal power plant is available. It should be interesting but I didn't do it.
Hot springs are not like Japanese onsens and allow public soakings for both genders, which means bathing suits, not birthday suits.
Try to visit the local restaurants during non busy times as a limited number of waiters are available and waits can be long for service.