In theory I could just move back to England, but right now I'm quite happy where I'm at. If a job opportunity came up, who knows?

If by socialist policies you mean ruled by a communist party then hell yes. It would be a dream come true to live in for example China.

It depends on the country as socialism covers a very wide range. If you look at Sweden and China they are very different forms of government.

One problem is the stereotypically ideal socialist countries -- the Scandinavian ones -- have very tough immigration rules

They also have unique circumstances around racial / cultural homogeneity and sovereign wealth / resources that help with cohesiveness and generous benefits -- and those can't be easily replicated

If I can keep my current quality of life or have a better one, sure.

Yup! My youngest son wants to when he is old enough.