Artizard

I'm a pixel count and display snob and really, really enjoy high resolution panels. Part of that reason is more pixels to fit more things on the screen. Increasing the scaling to make that 1440p display look the same as that older low res 1080p display, you're giving all that up. Yeah, you still benefit from the sharper image but you can fit the same amount of things on the screen and that's a huge negative for me. 
 
Hell, display on my laptop is 3200x1800 and only 13" so at native or 100% scaling, everything is very, very tiny so I only somewhat compromise and run a 125% scaling.
 
On normal desktop displays, I see no reason to run anything other than native 100% scaling. 
 
My display layout look like this right now.
 

 
If you game on that 1080p display, 1440p will now be an option you can select. Generally yes, gaming at 1440p over 1080p will lower your framerate though how much and if you care depends on your GPU.

I'd say you should drop down to a B450 motherboard and you should try and get some faster RAM. 3000 MHz or higher if possible
 
As far as the CPU goes, I'd say wait for Ryzen 3000 series if you can and if you can't then you should drop to a R5 2600 and overclock.
 
Also why would you pay $500 dollars for a GTX 1070 ti. Nvidia just announced the 2060 for $349. If it's even close to that when it launches next week then that's a way better deal given it should be giving comparable performance.

Unless you want the best overclocking performance, I would get a B450 mobo and save a few bucks.  I would also go with the normal r5 2600, not the x version since everything I've heard says that the 2600 overclocks about the same as the 2600x.  If you don't plan to overclock then r5 2600x is fine since it will be faster out of the box.  I also recommend RAM with at a speed of at least 3000 MHz.  Memory speed affects Ryzen a lot and faster memory will improve your experience with Ryzen.  Other than that, everything else looks good.
 
Edit:
I forgot to mention, you may want to wait before pulling the trigger on this.  AMD may be announcing the next generation of Ryzen at CES and if the rumors are true, there will be massive performance gains (although I am a bit skeptical).

You don't need "better" water cooling for that CPU. You'll hit the all core limit way before you could hit the limitation of that kit. Even the stock cooler is decent for it, I have used one for quite some time.

Though, I'm not a fan of those kits with alu rads. Build your own, and pick a waterblock that fits onto the stock backplate with just 4 screws rather than something else. They're easier to work with when it comes to this platform.

Spend 150-180 on a swiftech h320x
Buy another 240-360mm rad.
purchase enough fans for it so 2-3 fans at around 15-20 each (for good fans)
Purchase a gpu block for your 1080ti atm they can be found from 50-150 depending on deals and people getting rid of unused stock
grab 4 compression fittings and some extra tubing  $20 for box of tube and about 4-5 bucks per fitting for another $16-$20
 
So $300-$350 total cost and this will give you a decent cpu block, a great ddc pump, a good amount of rad space, high end gpu block, and best of all it will NOT be aluminum so you won't run in to the issues of combining metals or needing to search for aluminum safe components.