Rhoban

I would also take a look at the AD700X or AD500X (depending which one are in your price range). 
They are considered as some of the best for gaming. But don't expect booming bass. 
An alternative, but you will require a headphone amp, is the AKG K612 Pro. They have a big soundstage (bigger than the above AD series in my opinion) and also somewhat more bass. 
All of the above provide excelent sound positioning, but the AD series makes footsteps stand out more if that matters to you. 

Many articles mention a Q3 date. That would be this summer. 

In order to take full advantage of Ryzen 2, you would need a X470 or B450 chipset. XFR2, as far as I know, is only supported on those motherboards. 
 
XFR is like GPU boost from what I can tell. 

If you do get the 8700K, I recommend getting a Z chipset. 
Even if you don't overclock now, you might in a few years. 
 
Otherwise just get the 8700 non K. Performance at stock speeds is identical. The K is only worth if you will overclock it.
Not only will you save money on the motherboard, but also on the CPU. 

What about the MasterCase 3? 
There's a Fractal Design Focus Mini G too, which has front mesh panel. 
 
 
 
 

Yes. 
But for gaming I would recommend the i5 8400. 
It's currently the budget king. 
Intel also doesn't rely on RAM speeds as much as Ryzen. 

Why not go for the MasterCase 5? 
 
It seems to be very similar in design, except for the huge fan mounts in the front. 
 
I own the MasterCase 5 and it's a huge beast. Only problem is, it doesn't support top mounted radiators without a special bracket. 
The bracket can be purchased from Cooler Master or you can get it together with the MasterCase 5 Pro. 
Even then, you can only do a pull configuration. 
 
Other than that, I'd say it's a solid, future proof, case. 

http://thebottlenecker.com
 
@OP
https://docs.google.com/spreadsheets/d/1k6heVCRwhlR9aAHxY5TVrDlu_rPK-X5oaafIPNXuAMM/htmlview
 
This chart shows that your CPU would only bottleneck in a worst case scenario and you generally should not have a problem. 
 
As for a solution, an i7 7xxx or i7 8xxx is the only option. 

They will work. But it will need a bios update. 
 
Also, I read that Precision Boost 2 requires the new 450/470 chipsets. Don't know if it's true or not. 
 
 

64GB of internal storage might be a bit small

For future proofing your rig, a 1080 would be recommended. 
 
As games and graphics advance, the 1080 will push less and less frames over the years, eventually barley doing over 60FPS. 
 

The 1070TI is pretty much the same as the 1080.
Obviously, a 1080 is the best choice for future proofing, unless you can get the 1080TI.
 
If you can't get the 1080TI, then the 1080.
No reason to go below that. 1080 also wins against the 1070TI due to its faster memory.