Totally depends on your interests. If strictly wine tasting, then stay somewhere in the northern Haut-Rhin (between Kaysersberg/Ammerschwihr and Bergheim. A lot of wineries you might want to visit are a bit of a drive, but the drives are beautiful and it’s as central as you can get.
If there’s interest in culture and wine, then stay in Colmar. Advantage: walking to some very good restaurants, shortish drives to others, and most of the best wineries in the Haut-Rhin aren’t overly far.
If you’ve interests in the mountains, then Kaysersberg is perfect as it’s already 1/3 of the way up to the Vosges.
A truly ideal stay in Alsace would be: fly into Basel/Mulhouse, stop at Antony as it’s very nearly the best cheesemonger in the world, then drive to Colmar/Ribeauvillé/Kaysersberg/wherever you’re staying, taste wine and tour villages and go to the Unterlinden, then head north to Obernai for a few days and do the same, then finish in Strasbourg. Maybe ten days, if you’re efficient. Two weeks if you’re into relaxing.
You’ll want to rent a place with a kitchen at some point because you will not, unless you’re there for white asparagus season, have a vegetable otherwise.
I’ll say that, for myself, staying in Colmar (or Strasbourg, or Mulhouse) was nice in terms of walking back from wine-soaked dinners and for groceries, but staying in the smaller villages was immensely more rewarding. So much more peace and quiet. Do some restaurant research and pick one with a few options, then stay there. That’s my best advice.
Quaintness: Kaysersberg, Ribeauvillé, Eguisheim, Turckheim, Bergheim, Obernai. Really, though, there are few villages in Alsace that aren’t charming. (Ammerschwihr and Epfig are two.) You can hardly go wrong.
Hotels: I’ve mostly rented gîtes, but in the past I can say that one of the best hotels in Alsace is Le Parc in Obernai. Lavish, fabulously expensive, good restaurants and bars inside (when I was there, it was totally traditional; it’s very much not anymore). I’m sorry I don’t have more recs for you, but I’ve always rented places so I can drink the wines I’m buying and have the occasional f-ing vegetable!