You need to figure out what things and activities are most important to you. Of the 4 locations that are available to you, they all have very good, well established accommodations like restaurants, big box stores, sporting good stores, etc., but not all have good/easy access to everything in regards to outdoor activities. My personal opinion (and I'm sure it's bias because I live here), is you can't beat Anchorage or the valley (Wasilla/Palmer). The mountains around this area are absolutely beautiful, there's tons of outdoor stuff to do, like hiking, backpacking, camping, Alpine and Nordic skiing (I think Anchorage has the most groomed/lighted cross country ski trails in the world), fishing, hunting, ice climbing, and the list goes on and on. For sure, the best salmon fishing is down in the Soldotna area, but that's only a 3-4 hour drive from Anchorage or the valley. Anchorage and the valley are very centrally located, with pretty much the best of everything being either, right in the area or a pretty short drive away. Again, this is for the 4 places that you listed that are available to you for employment. The price of housing is cheaper in the valley (you get more for your $$), but a lot of folks in the valley work in Anchorage, and the commute can be a bit of a buzz kill. If you're commuting during rush hour and there's a fatality on the hwy, there's a good chance that you won't get home for several hours because there's only one way in and out, and they usually close the hwy for 4-5, and even 6 hours ,in the event of a fatality. Anyway, that's my take on it. Good luck if you do decide to make the move up.
