First Build General Advice (~£900)

Hi, I'm looking to build my first gaming oriented rig (also general use at uni) in the near future after putting it off for the last half a year or so. I just wanted to ask some for some basic advice to maximise my spending and performance with a base budget of £900, maybe up to £1000 at a stretch. Honestly, I'd rather cut down to £900, as opposed to the £950 it's at now, but I wouldn't know where cuts (if any) are most ideal.
Below are my thoughts about each specific part I just wanted to go through each and briefly-ish explain why I thought they might be suited for me.

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Current Build:
PCPartPicker part list: http://uk.pcpartpicker.com/p/N6CGHx
Price breakdown by merchant: http://uk.pcpartpicker.com/p/N6CGHx/by_merchant/

CPU: Intel Core i5-4690K 3.5GHz Quad-Core Processor (£167.50 @ Amazon UK)
CPU Cooler: Cooler Master Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler (£24.97 @ Amazon UK)
Motherboard: Asus Z97-PRO(Wi-Fi ac) ATX LGA1150 Motherboard (£141.54 @ Amazon UK)
Memory: Corsair Vengeance 8GB (2 x 4GB) DDR3-1600 Memory (£64.00 @ Ebuyer)
Storage: Samsung 840 EVO 120GB 2.5" Solid State Drive (£54.95 @ Aria PC)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive (£39.99 @ Amazon UK)
Video Card: Asus GeForce GTX 770 2GB DirectCU II Video Card (£262.98 @ CCL Computers)
Case: Corsair 300R ATX Mid Tower Case (£56.27 @ Amazon UK)
Power Supply: XFX 650W 80+ Bronze Certified Semi-Modular ATX Power Supply (£62.78 @ CCL Computers)
Optical Drive: Lite-On iHAS124-04 DVD/CD Writer (£13.15 @ Amazon UK)
Operating System: Microsoft Windows 8.1 (OEM) (64-bit) (£71.60 @ Amazon UK)
Total: £959.73
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2014-12-13 17:48 GMT+0000

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Firstly, the CPU I'm happy with - the 4690K seems to be the go to option and there's no issue with it. I don't plan on overclocking straight away but it's nice to have the option.

The 212 Evo fits with my budget nicely and appears to be a good for a balance between airflow and noise.

The mobo I slightly question: Choosing the Z97-Pro I have selected the wifi version simply because I don't have access to ports right now and I want to be covered in case at uni I don't have any access there. The board seems good to me, maybe even beyond the other components (maybe I should even spend less on this and focus spending elsewhere?)

The RAM is particularly problematic in my mind. I listed the Corsair Vengeance 8GB simply because its highly rated, popular and I know it works. However, I there are much cheaper alternatives and my build isn't exactly a monster to justify spending this much on 2 sticks of 4GB really when I could get it much cheaper. Also, the speed being 1600Mhz sounds a bit underwhelming when other brands offer 1866Mhz cheaper.

In terms of SSDs and HDDs I plan on running the OS off the SSD and everything else off the HDD, pretty standard really. The Caviar Blue is nice and cheap, but is the 840 Evo the best offer here for 120GB?

For the GPU I'm looking at a 770 since it puts the price of the whole build to around the £900-£1000 mark. The Asus DirectCU II sounds decent but I have seen other builds where the budget is significantly more skewed to account for something like a 970, but whether that would compromise the quality of other components or make it run less stable I don't know. (Just to note on the whole Nvidia vs AMD debate I'm open to AMD options too)

The case is also another point where I'm wondering if I'm looking at the right component. The 300r, from what I can tell, is a simple enough mid tower case with good airflow and a nice amount of space. I honestly prefer it aesthetically to the plastic looking cases with edges everywhere; to me they look kinda tacky, but am I better off with something cheaper? (for example the 200r is basically the same but inferior in basically every sense, but do I really need amazing airflow for a rig like this)

The PSU I think is good, the tiers of PSU on the newegg forum listed it in Tier 1, although it doesn't seem that popular here in the UK. After hearing that some supplies like the Corsair CXM 600W are actually not that great I was advised toward this and so its made the list.

Optical Drive - nothing to be said really, its cheap and does the job.

I'm fine with running 8.1 for the OS though it does seem pretty expensive. Also, is there a major advantage over the OEM version instead of the standard retail? I think the difference is that it's tied to the mobo, but I fail to see why that's an advantage unless I haven't realised a significant price gap.

That's essentially it, sorry it's far too long; I just wanted to get my current thoughts and issues down while it's fresh in my mind.

Thanks