Here's how I'd spend your fortune:
PCPartPicker
Perhaps a gaming build would've been good enough with a much lesser motherboard, an i5 and 8GB of RAM, but you got money to burn, so what the hell.
Don't let the 650W scare you, it's a Seasonic inside, and a very good one. It's plenty even with some serious overclocking, or SLI w/o OC. And it's super-cheap all things considered.
Now for the things not on the list:
Monitor: I recommend Eizo's brilliant
Foris FG-2421. It's a native-120Hz MVA panel (not TN!), and it performs remarkably, is solidly built, and just about the only thing I'd fault it for is not supporting rotation into portrait mode.
PCBuyIt carries the monitor for just under 420 GBP inc. VAT. You could get it a bit cheaper from
here, though shipping price and waiting time might make that deal considerably less sweet.
Keyboard: I recommend the
CM Storm QuickFire Ultimate w/ Cherry MX Browns. Full LED illumination (selectable color), good build quality.
Microphone: The
Plantronics Audio 300 is a fantastic mic, I had the pleasure of using it, and it's sound quality is really great, plus it's noise cancellation is nice and efficient. It's also dirt-cheap.
I left the optical drive out, 'cause who needs those anymore? If you really want one, I suggest you grab an external USB drive which you'll only plug in when needed, then store away, or carry with you, if you're so inclined.