Food will be more or less the same all over Germany if you cook for yourself and shop in discounters (like Aldi).
Apart from that, Zwickau will probably the cheapest (former eastern Germany), Furtwangen is basically in the middle of nowhere (especially in February), Ulm is a bit 'spie?ig' (middle-class) and probably the most expensive area, but might offer the best reputation - not at least because Ulm university is working together with several hospitals directly in Ulm, including one of the German Army hospitals.
As for newcomers - eastern Germany has a reputation for being quite a bit right-wing and opposed to foreigners, though I've no personal experience. Both Black Forest and Schwabische Alb are used to tourists, but in either place you won't understand a word once the locals start talking in their respective dialect.
As for community - as I said, Furtwangen is in the middle of nowhere, without (acces to) a car you'll probably be stranded. Ulm has local entertainment and concerts as well as being situated on the main railway line between Stuttgart and Munich.
It'll boil down to (as usual) 'you get what you pay for'.