First ever Gaming PC build Advice

Solution
It would work fine, but you have some overkill going on in some places and less so in others. My thoughts are below...

CPU COOLER - A good air cooler will do just of a job, or better, for less cost.
MB - That board does not support SLI. For not much more you can keep your options open for adding a second GPU in SLI down the road.
MEM - The Z270 chipset is fine with faster modules. Just try not to go past 1.3v modules.
SSD - The Samsung EVO is nice, but not at its current cost. Look toward SK Hynix, Crucial MX300, Sandisk X400 or the WD Blue for good performers at lower prices.
GPU - Similar factory overclock for less cost with the EVGA below. Both have good cooling solutions.
PSU - Changed to a 750w unit to cover the potential...
It would work fine, but you have some overkill going on in some places and less so in others. My thoughts are below...

CPU COOLER - A good air cooler will do just of a job, or better, for less cost.
MB - That board does not support SLI. For not much more you can keep your options open for adding a second GPU in SLI down the road.
MEM - The Z270 chipset is fine with faster modules. Just try not to go past 1.3v modules.
SSD - The Samsung EVO is nice, but not at its current cost. Look toward SK Hynix, Crucial MX300, Sandisk X400 or the WD Blue for good performers at lower prices.
GPU - Similar factory overclock for less cost with the EVGA below. Both have good cooling solutions.
PSU - Changed to a 750w unit to cover the potential second GTX 1070 added in SLI down the road.
MONNITOR - 1080 resolution is a bit low to let a GTX 1070 stretch its legs. Instead of a 1k display at 144Hz, consider a 27" 2k display (1440 resolution) at 75Hz.

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-7600K 3.8GHz Quad-Core Processor ($234.49 @ OutletPC)
CPU Cooler: CRYORIG H5 Ultimate 76.0 CFM CPU Cooler ($56.49 @ OutletPC)
Motherboard: MSI Z270 SLI PLUS ATX LGA1151 Motherboard ($139.99 @ B&H)
Memory: G.Skill Ripjaws V Series 16GB (2 x 8GB) DDR4-2800 Memory ($106.99 @ Newegg)
Storage: SK hynix SL308 250GB 2.5" Solid State Drive ($82.99 @ SuperBiiz)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($49.33 @ OutletPC)
Video Card: EVGA GeForce GTX 1070 8GB SC GAMING ACX 3.0 Black Edition Video Card ($379.99 @ Jet)
Case: NZXT S340 Elite (Black) ATX Mid Tower Case ($89.99 @ SuperBiiz)
Power Supply: SeaSonic G-750 750W 80+ Gold Certified Semi-Modular ATX Power Supply ($89.49 @ SuperBiiz)
Operating System: Microsoft Windows 10 Home OEM 64-bit ($92.99 @ B&H)
Monitor: Asus PB277Q 27.0" 2560x1440 75Hz Monitor ($315.72 @ Amazon)
Total: $1638.46
 
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