I think your lifestyle here will depend on your jobs and budget. How old are your DC?
Some of your comments about uk life are quite offensive to me: materialism, doing up houses, cleaning, career ladders, shopping and talking about TV shows. Those things have never been my life, either when I was young or now in my 60s. Florida may have a sunshine lifestyle and high standards of living but the lack if culture compared to the UK would make me die inside. What do you talk about in Florida? Pool boys and chemical maintenance?
We have a 2nd home in Southern France and as we get older hope to spend more time there. Life is a different pace there and it's beautiful and the food is better. France is also better run, has better schools and much better healthcare. It is far less densely populated. But in some ways more parochial and far more bureaucratic.
However, the things I love about being in close proximity to London are: opera, concerts, theatre, art, etc. I couldn't live without that.
I suspect you will find your lifestyle too great a compromise to return. In the South an average house is a 3 bed semi, not much garden, two bathrooms if you are lucky. Probably £500k; in London closer to £1.2m; nice home counties £800k ish (Bucks, Surrey, Herts, etc).
What do you value about a UK education particularly?
The UK may be "grey" but it is also very verdant.