For what it's worth the jump from the 750W PSU to the 850W PSU is only £17. Of course it all adds up so for now I've gone back down to the 750W unit since I've moved away from the more power hungy(?) i7 CPU but I may still change my mind and just go with 850W so I'm future proof.
I've also dropped down to the PCS FrostFlow 150 (again, because of the CPU change).
And I've dropped the DVD writer as it's true that there really is no point getting that from PCS (except it's pretty cheap and nice just to have everything arrive in the one delivery right? so again, I may change my mind in the end).
The final aspect I just want to ask folks about a bit more is storage.
The model I have in my head from my current PC is a fast C: drive (excuse me using C/D here but hopefully we all know what I mean) for Windows and games like Elite where I really want files to load quickly, and a big/reliable D: drive (speed less important) for storing everything else that builds up over time (home photos and videos, Elite Dangerous videos, games I don't care so much about, etc). I think this model comes from a simpler time where there was HDD and SSD and you stuck Windows on SSD for fast boot and everything else on the HDD ... and then I shifted Elite into the SSD because I read it could improve performance.
Anyway, Morbad has given me pause for thought on this model. What do I mean by "games I don't care about" anyway? I don't have a massive games library but I do have a bunch of VR games and a small Steam library and I plan to get Cyberpunk and who knows, maybe even Star Citizen. Perhaps the model of a big fast D: drive for my games (plus incidentally all that other archival photo/video stuff) and then a separate drive (SSD obviously but less performance tuned) for Windows makes more sense?
What do other people think? Seems an interesting sub-topic.