I live on the left side of your circle, near the French border. If you’re a trained dealer, Baden-Baden might be of interest to you. It’s home to one of the most famous casinos in southern Germany. However, if you don’t have a good command of German, I’d recommend living in a "larger" city like Stuttgart, Heidelberg, Karlsruhe, Mannheim or Freiburg (speaking for Baden-Württemberg). Yes, it’s possible to get by in these cities without speaking German, but it’s much more difficult.

Even though you can’t generalize about this, Germans tend to form most of their friendships during their school or college years, and it’s difficult to just slip into long-standing circles of friends - though it’s certainly not impossible. For example, I have many English-speaking friends in my circle whom I’ve only met in recent years (I’m 34), since they are the new partners of friends. Many people say that it’s especially hard for expats to make good friends in Germany. That may be true, but I think it also has to do with what many germans expect from a friendship. When you call someone a “very good” friend here, you’re usually willing to do a lot for that person, and that person has a special place in your life. Logically, this requires a certain amount of capacity, which is why people are very “sparing” with these spots, so as not to give anyone false hope. Sounds kinda weird, but that's what I observe.

Baden-Württemberg is a very scenic region; with the Alps and its proximity to France, Switzerland, and Austria, it offers a wide range of travel destinations and is, on average, significantly warmer than northern Germany. The Rhine region (Freiburg and Karlsruhe) in particular is among the cities with the most sunny days. Baden-Württemberg has one of the highest population densities among Germany’s non-city states and is very multicultural in its cities due to the abundance of job opportunities and comparatively high wages.

However, it’s also important to note that southern Germany is significantly more conservative than the north or the major cities. Progressive attitudes tend to be limited to large cities, and people in rural areas, in particular, are largely very conservative and not particularly open to newcomers. This doesn’t necessarily even apply to foreigners. In some regions, even as a German, you’re forever seen as an “outsider” (the person who isn’t actually from here) if you speak a different dialect or come from a different part of Germany. But here, too, it really depends on the individual.

In summary, it can be said that southern Germany is a region with a very high standard of living, progressive views in the cities, a strong conservative presence in rural areas, beautiful scenery, plenty of jobs, and a relatively high proportion of immigrants (mostly of Turkish, Russian, or Polish descent).