I had one of the most unexpectedly pleasurable rounds in a long time at Thorndon Park (Essex) yesterday. SE England is currently enduring a heatwave, so the course was almost deserted, but I was really impressed. Posh parkland isn't normally my thing, but for a sense of space and serenity and the usual Colt-esque intelligent green designs barely 10 minutes from the M25, Thorndon Park ticks a lot of boxes. And there is simply masses of room, in part because over the past decade 3000 trees have been felled on the property. The other, pleasingly old-fashioned aspect is that the golfer is always moving forward from green to tee.
I can't find much discussion of TPGC on GCA for (at least) the past 15 years, but for those heading out of London towards Suffolk, or simply looking for somewhere a bit different (and notably cheaper) than the usual Surrey/Berkshire suspects, I would warmly recommend having a game at Thorndon, even if the clubhouse (in the shadow of the old stately home) has a rather low and airless main room as its central feature.