On a £1000 budget, I would say an R3 or a 690 II Advanced Dominator, but it is down to preference, and is usually one of the last things you chose. As for the rest, it really is personal opinion. I hear a lot of hype about mechanical keyboards... But they aren't cheap.
Branded PSU's are always the way to go. Corsair do good solid PSU's. Mechanical Keyboards have been hyped on here there is thread thats got several posts in it. All discussing Mech KB's. But your talking over £100 or so. I'd get one but don't feel the need for it right now. Headsets wise it's down to personal preference. ASUS Vulcans have been well received though I don't own one myself. Case yet again is personal preference there are some beastly ones out there. I have a HAF 932 Advanced and I like it but wouldn't say I love it. Though it does do what it needs to do.
I did sorry, but what I meant was why did you settle on those figures as guesses? I was just wondering if that was comparable to the overclocking potential increase in the last Tick? Just curious!
Well if you look at the chips in 45nm fab process and they'd be around 4Ghz/4.2Ghz i.e. i7 920/930's etc, while although sandy bridge was an architecture change we had already seen clocks of 4.6 on 980x's the only really high end chip that intel released on the 32nm fab process, I believe the others where i3's. Then we have SB come along with most chips able to hit 4.7/4.8 pretty easily and Ive seen a good number at 5Ghz + also I have seen an i7 3770k at 7Ghz, obviously it was using crazy voltages and LN2 and probably true, essentially what I said is a bit of logical guess work going from the fact that although we don't have an Arctitecture change we do have 3d transistors and a 22nm fab process all at the same time, also a higher multipler ratio I believe it's 63 now also helps (Y)