Finalizing build, would like critique

[Silorn]

Hi guys! So this is my first time building a computer, my previous computer had the parts selected by a friend and then was built by a company, but this time I plan on doing the whole thing myself with a little help from youtube. I've been researching parts as best I could. The reasoning behind having two storage drives is that I'd like some redundancy between the two drives without needing a full backup. PC Part picker notes 3 possible incompatibilities which were:

Doesn't know if the gpu will fit - not an issue as the card is the same size as my gtx580
Doesn't know if the NH-D15 will fit - I did some measurements and it should fit, although it might be a bit tight.
Motherboard has an onboard USB 3.0 header but the front ports on the case are 2.0 - will likely buy this adapter to counter that issue.

Budget: Would like to keep it around 1500 euro as I need a new monitor + keyboard also (outside of the 1500), but could go higher with good reasoning behind the increase in price.

Resolution: Currently play at 1080p@144hz, would like to play at 1440p@144hz or 60hz for the latest triple-A games

Games / Settings Desired: I'm not too concerned about playing at Ultra, I'd prefer to keep it at 144hz than max settings.

Any other intensive software or special things you do: Some streaming / video recording.

Country: Ireland, anywhere that can ship to Ireland/UK is fine.

Parts that can be reused: I have Windows 7, a PSU, a Case and an SSD (included in parts list) that I believe can be reused, although I'd like feedback on whether I should reuse the PSU as it's about 5 years old at this point.

Do you need peripherals? Recommendations for 1440p monitors would be appreciated, I need a keyboard also but I've been pretty dead-set on getting a Corsair K70 for quite a while so any deals on that would be also appreciated.

Currently planned build:
PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-6600K 3.5GHz Quad-Core Processor (€264.91 @ Mindfactory)
CPU Cooler: Noctua NH-D15 82.5 CFM CPU Cooler (€93.32 @ Mindfactory)
Motherboard: Asus Z170 PRO GAMING ATX LGA1151 Motherboard (€147.84 @ Mindfactory)
Memory: Corsair Vengeance LPX 16GB (2 x 8GB) DDR4-2666 Memory (€111.32 @ Mindfactory)
Storage: OCZ Vertex 4 256GB 2.5" Solid State Drive (Already Owned)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive (€52.89 @ Amazon Deutschland)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive (€52.89 @ Amazon Deutschland)
Video Card: MSI GeForce GTX 980 Ti 6GB Video Card (€730.52 @ Mindfactory)
Case: Cooler Master Storm Sniper ATX Mid Tower Case (Already owned)
Power Supply: Corsair Enthusiast 850W 80+ Certified ATX Power Supply (Already owned)
Total: €1453.69
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2015-12-06 14:11 CET+0100

Any input would be much appreciated as I plan on ordering the parts fairly soon so I can have them all by Christmas! Thanks for reading.

[Denpepe]

Your setup seems t be pretty decent, 2 things come to mind, if your PSU is really 5 years old I would think about changing, you don't want the thing powering your whole pc to crap out and secondly you could look into AMD cards like a 390x or fury, as far as I know they perform decently on 1440p and they have better DX12 support which is not that important right now, but will be in the next few years when more games will support it