I've moved countries many times, my last move was UK-Germany.
Good - better salaries, better hours, culture and education are much more appreciated than in the UK. Great public transport and choice of activities and days out, price of living somewhat lower and I'm in a big city. Country is in a pretty good shape financially and the health system is a bit tricky to understand but effective and modern. Beautiful countryside and mountains, coast... So much green space even in cities. Very outdoorsy lifestyle. Quick access to almost any country on the continent.
Bad - lots of bureaucracy, rigid customs and traditions (on Sundays the country basically closes down, there are also set rest hours during the day, etc). Not easy to integrate into the community, food isn't amazing and the weather isn't great either.
I'm an EU citizen so moving here was extremely easy from a paperwork point of view. Finding a place to live is a nightmare. Setting bills is a nightmare. Registering with the council and health insurance, cars, schools, taxes - all a nightmare. You need a lot of initiative and patience when arriving here.
Don't even think about it without a good level of German. I've been here over a year and my German still isn't great, it holds me back massively. You can get away with English but people don't appreciate it when you don't make an effort (and quick).
I love it here from a professional point of view, it's the best country to be in for my job. I might move somewhere else in 2-3 years if an attractive opportunity arises, but from a practical point of view, Germany is a great place to be.