We moved out of the UK a few years back...some of the folks here have made some very pertinent observations.
Tax - situation may change wherever you go for better or worse - don't move just because of the Tax situaion.
Commuting - I second cavorting Glueballs comments about it eating up your spare time. Commute to/from somewhere which is served from your base airport and has a high frequency of flights. As an example if you are LHR based Nice makes lots of sense but Toulouse doesn't.
Finally living somewhere full time is not the same as going there on holiday. France is wonderful if you are not trying to get stuff done in a hurry, in fact it often best not to do anything at all....but you don't find that out until you actually live there.
Then again, I've just spent a couple of days in the Pyrennees, along with 100,000s of other nutters, waiting for 150 odd lycra clad idiots peddle up a couple of mountains. Scenery to die for, a hangover I nearly died from, thanks to some Basque supporters, and nobody stops you painting slogans on the road - in fact if you ask nicely the rather nice lady Gendarme
will make sure you don't get run over while you are painting. T'would never happen in the UK so on balance it's a
from me...but the commutes still a b***r