London commutable location options for £650-750k budget

We're starting to explore the outskirts and commuter towns / villages of London in an effort to find somewhere that ticks as many of our boxes as possible for our budget. We've set a budget so as not to overstretch ourselves too much but have been quoted mortgages in the £1-1.2m territory.

We are looking for countryside living within a 1 hour commute to London in a perfect world. We really want green space and am willing to drive in most cases. 3 bedrooms is our minimum.

As with any property search I fully expect not to tick all our boxes. Commuting costs aren't a massive issue for us, it's more about time.

I work central and my partner works out West, and that probably won't ever change. King's Cross is a good option it feels, otherwise Euston or Paddington, Marylebone if my partner can drive in.

I would prefer a 1 hour commute door to door, but happy to do 1 hour 15-30 mins tops.