You don't mention if you speak any languages other than English? Whilst you'll get by OK in any large city with just English, some places are better than other

You don't mention if you speak any languages other than English? Whilst you'll get by OK in any large city with just English, some places are better than others. For example, in my experience, Lisbon (and Portugal in general) has a much higher level of English than Barcelona. Maybe language isn't a huge concern for you but you still have a level of bureaucracy and settling in moving to any new place.