Here's a great article on what's required to get a freelance visa in Germany (i.e. you don't actually even need a German company to employ you before you move): https://medium.com/@imcatnoone/how-to-get-your-german-freela...

My impression from visiting and friends that live there is that Berlin is undergoing a true technology renaissance at the moment. Personally, if I weren't already living in a perfect location, I'd be looking to move to Berlin.