Just my opinions. Grew up in Sweden (Gothenburg). Started moving around on my own in my late teens for work, studies, research, love, etc. Have lived in quite a few places over the years.

Moving to a new place is not difficult. Just don't bring a lot of baggage, neither physical nor emotional. Don't pack lots of expectations and opinions. Adapt fast. Expend serious effort to make a lot of new friends immediately, there will be some uncomfortable moments, most people are genuinely nice.

These are the countries (regions) I generally recommend and would move back to:

Switzerland (Zürich-Zug-Liechtenstein), Norway (Oslo), Denmark (Copenhagen), Sweden (Gothenburg), Netherlands (Amsterdam-Rotterdam-Utrecht), Japan (Tokyo).

These are the countries (regions) I would need a strong reason to move back to:

USA (South East states), Germany (München, Frankfurt, Konstanz).

These are the countries I avoid, recommend against, and would need very strong reason to move back to:

France (Grenoble), Spain (Bilbao), Cyprus.

These are the areas I'm keeping an eye on for future possibilities. Just for fun, from my limited knowledge:

Auckland, Vancouver, Singapore.

Just my opinions, based on my values and what I want in life. I love nature and want easy access more or less daily. I want a clean environment wherever I go. I want functional society that does not drain my time with bullshit nonsense. I am ultraliberal and want to have an easy time to find many other well educated and active open minded people.