I'm not planning anything elaborate or any trips for the Christmas weekend itself, though I work evenings both of the dates you're in town (middle of the day works, or for dinner, I might be able to scoot away for a short bit but not for too long...). It's in your honor, so figure out what works better for you and we'll get a thread in Community going on!
Certainly the 22-24 DEC period would be better, I would probably be in much better condition, so to speak. As just mentioned I'm not against doing something when I arrive either.
Both are fairly new (built in the last 6-7 years?), so both are more than decent. SpringHill Suites is in the Midtown area next to the Century 16 Theater but not within walking distance of much else in car-centric Anchorage
The Marriott website says the Outback and the Bagel Factory are within 1/10 of a mile. I took a look on Google Maps and it looks like the Outback is just across the street. Other than that, it doesn't seem like much else is within a short walk. I looked at the SpringHill Suites because it was closer to the airport and I figured there wasn't much going on downtown that made it worth staying there, especially for the first overnight.
If there were a compelling reason to stay downtown, I would probably take it. The only thought I had was maybe being downtown would have a better choice of dining options. I've got my 17 year old daughter with me, so I like to keep my options open.
If you're without a car, though, and we decide to do a get-together at a place not in walking distance from wherever you're staying, I'm sure one of us would be more than willing to offer a ride (I'll do it, but my car's usually so dirty--a typical college-student car--that you might want to take someone else up on it if they offer

.)
I will have a car for the second visit, I just didn't think there was a need for the first overnight when I was just planning on going to/from the hotel to the airport. With a car and the Springhill suites, I think I'm in a good location to do whatever we need to do. I'll probably do some last minute shopping before we head back to Germany and pick up a couple of Alaska touristy trinkets for some friends.
When visiting Europe (though I haven't been since 2001), I usually fly into either MUC (friends formerly in Rosenheim) or STR (friends in Albstadt and Lindenberg im Allgäu), so I could foresee myself being in Stuttgart again someday!

Thanks for the offer!
If you ever do make it, let me know. I'll drag you around Stuttgart to some of my favorite spots.