I made the move from Wandsworth to Petersfield 5 years ago having lived in London all my life. I moved in my 50s.
Petersfield is an excellent market town with good train links into Waterloo - circa 1 hr 6 minutes on the fast train, or 1 hour 25 minutes on the slow trains.
A vibrant market town with good shops - Waitrose, Tesco, M&S Foods, Waterstones, Smiths, Boots, Superdrug etc etc plus independent shops and restaurants.
Winchester is also a lovely place as well though I don't know as much about it.
Your budget will get you a good house in either.
But London it is not. Public transport is limited to trains and infrequent buses that finish early. No TFL here. No ubers here. Taxis are expensive.
The pace of life is slower, Petersfield has an older resident vibe. It isn't diverse like London. Just like everything there are pros and cons.
It's slap bang in the middle of a national park so there is beauty on your doorstep. It's an easy drive to a variety of beaches. Easy to get into Guildford for a bigger shopping experience, or Chichester.
On a normal day it's about 35 minutes up the A3 to the M25 junction. It takes me about 1hr 15 minutes back to Wandsworth/Wimbledon etc. on a Saturday with traffic. The same to Gatwick airport.
I still miss London and I find it a pain getting the train back in the dark in the Winter when I visit friends for lunch in central London. But that's just me. My partner travels into London 2 days a week and many do the commute 5 days. I work from home.
Do you enjoy the countryside, seaside etc?
My one tip coming from London is to pick a proper town that has all the amenities that you would want from a move. It may look lovely in a small village but there are severe limitations that come with that.
I would look at these places as well as Petersfield and Winchester - accepting these are in Surrey ...
Haslemere - though the High Street is lovely there isn't actually much there
Godalming
Farnham