Pluses/minuses for each: AKL – lots of activities, including practically having a zoo at your resort; very close to AK park; great restaurants at the lodges; unique atmosphere for a resort; certain rooms are among the largest at WDW. SSR – very close to Disney Springs, which give you great choices for meals outside of the parks as well as other entertainment options; Treehouse Villas are kinda cool to stay in; otherwise, rooms are some of the smallest at WDW; nice, traditional resort atmosphere.
Bus or car travel to the places other than what I have mentioned from each resort will be about the same, with maybe a couple of minutes edge going to SSR.
It really all boils down to how much time you will spend away from the parks, and what you will do with that time. If you plan on just staying at the resort, I would suggest AKL (also, it greatly reduces travel time for one of your park days). If you want to spend time shopping and have different meal options, or plan on spending a lot of time at Blizzard Beach, then I would suggest SSR. As much as we like Disney, 14 park days would be way too many for us, so you should use that for your basis for a decision.