Depends a lot on what you like, what your hobbies are etc.
For example if you like not being miserable, don't go to Munich, people there suck (in my experience, and also the experience of all my German and Dutch friends, Munich people are on average less friendly compared to people in other big cities, of course there are friendly and rude people everywhere).
Stuttgart is the ugliest place in Germany and everyone who lives in Frankfurt is either an investment banker or a heroin addict (or both).
So among the big cities, I'd probably recommend Cologne or Hamburg. Cologne people probably have more local pride overall (as in, they all identify with their city a lot, doesn't mean they don't accept outsiders or foreigners, they tend to be very open, unless you're from D*sseldorf), and they are crazy about football and their local football club. While football is also pretty big in Hamburg, if you do like football, Cologne is probably one of the best places to be, because NRW (the state that Cologne is in) has a very high density of fairly successful football clubs. Cologne also has the Gamescom every year, idk if you're into that. I haven't been to Hamburg much at all, so I can't really say much about it tbh.
Do you speak German?
If you wanna live in a big city, go to Cologne or Hamburg. But to be honest, finding a reasonably price for a place is VERY difficult there because, well, theyre big and have a good reputation so demand is skyhigh(which counts for nearly every big city in Germany because our gov isnt that great at building more houses for the people).
Also, what do you define as a small town? Because there are a good amount of mid-sized cities that are pretty neat(Karlsruhe, Freiburg come to my mind f.e.)
I made an account, just to tell you, to not move to Germany. Unless u plan to stay unemployed and live from social assistance, Germany is a very bad place to earn money, because u pay the most taxes then everywhere else in the World.
Also Healthcare is not free, you pay a certain amount every month from your income and then in the end of the Day, the Healthcare system is just very bad (staff shortage).
I could list a lot more reasons, but me as a german are actually thinking of leaving the country.
And yes Düsseldorf is dogshit (i am from Cologne).
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