Depends how much you like rain. If you do then you're going to the right place. You're pretty much guaranteed rain on the track day in U.K. Unless it's too freezing to rain. Most probably the day will go so you get a whole lot of wet track to yourself or an expensive day talking crap in the garages.
Go to southern Spain for the dry weather options.
Portimao gets a bit of rain also but I've never had a drop there. best/easiest surf in Europe too is in the area.
On most events you can do paid instruction from ex gp/wsb winners. They'll tell you: more gas earlier and use less brake
Track sense cost a bit more and don't have so many events but also are the best organised, I've done a few with them in recent years.
Focused get the most events but are pretty rough so haven't done any with em for a few years.
Nolimits are a safe bet so I did 4 euro events with them this year, Aragon, Portimao, Spa and Cartagena.
MSV own the tracks so only do local at their track events.
Euro organisers bike promotion and bikers days are good but i've only done them non direct and through no limits.