IMTECH :
Yeah, you are right. We can tone down on the PSU. Still, I wouldn't change other parts. Liquid cooler is not necessary - air cooling is easier to set up and maintain. 212 EVO is a decent cooler, I don't see the problem. It will keep the processor cool and run quietly. 6-core processor is also not necessary, imho. i7-6700K has a way higher base and turbo clock which is more than enough for gaming.
If VR is your goal, having the higher end processor is definitely a necessity. VR has changed the way games use CPU architecture, and it's not in our favor. It's made games very CPU intensive. The days of "oh hex cores and multi threaded CPUs are useless for gaming" are over. VR and even 4K have changed that. And yes, the cooler is a problem. It's cheap, difficult to install and very outdated. It *WAS* a great cooler and I've used several of them, but now there's much better coolers that have come along since then. Yeah liquid isn't necessary but you've got £3500 for your budget, and spending nothing on cooling makes no sense. Without proper cooling, that £3500 PC is an £3500 paperweight.
Your information on cooling is outdated. There's lots of coolers that have come along since the Hyper 212 Evo and D14. That does not mean that those are bad coolers, but much newer CPU coolers have come along since then that are cheaper and more sufficient, while liquid cooling is getting better and more reliable with each generation of liquid coolers that is coming along. Newer liquid coolers and radiators like the Cryorig A80 and EKWB Predator are leaps and bounds above what was available in that area 4 years ago. I suggest doing some more research.