I think @Need a PhD in TV has probably said enough for you by now…
… but I also say go with the 936, certainly for picture quality and ambilight.
I paid £2000 for it, but have had it since last October and still happy I did so - and I didn’t even connect the soundbar as it gets in the way of my AV System centre speaker. So for times when I don’t want a room full of sound, or the heat of the AVC during a heatwave, I had to buy a low profile one from Yamaha :-&
To add to your other questions…
… I don’t have any real issues with the TV now, there were a few sound issue with ARC/eARC but that was sorted after a month or few. I prefer the Atmos sound and maybe picture using a 4K Gen 2 Apple TV, well I did until a s/w update to it causes occasional massive clicks and pops so back using the inbuilt TV Apps for Netflix and Apple TV+.
… My TV is typically on for at least 5 hours a day with someone watching, longer at weekends and special items like Wimbledon in 4K HDR on the iPlayer, Glastonbury, probably some of the Commonwealth games next. I have the Enhanced local image protection on default as I don’t use it for gaming and it doesn’t get in the way if the football scoreline dims a bit. I don’t seem to suffer from HDR whole screen dimming issues as others do (maybe just 8x6 TVs) and after a couple of months I rarely get the pop up message to turn off to recover potential screen residue issues - it’s normally close to the end of day so I let it wait until I turn off the TV to standby for the night. Depending on use you may see this message, so for the first few weeks to a month or so I’d let it do this when it asks, 20 minutes seem enough - it will tell you if it needs more time. So far the EVO screen is pure with no visible shadow/shape issues at 5% white levels that some folk with 8x6 TVs get.
… With any expensive TV I’d suggest you get a long warranty - Richer Sounds extended the 2 years from Philips to 5. Note, all warranties seem to try and get out of screen burn, so best to keep an eye on it. Search the Web or YouTube for 5% white OLED examples or screen burn for more info.
Would I wait for a 937, well if I still had my previous 9002 I might but you can’t keep waiting. I was happy enough with my four year old 9002, until I knew I‘d really see a difference with a 936 with its EVO. The EX doesn’t seem to be a quantum leap for my use, non-gaming. I doubt the current mostly streamed material I watch would benefit from it, even with the anticipated new Apple TV out, probably, this September.