I like the concept and the look would go well in my own Home Theater environment. I use a lot of black metal and glass for a modern look and this would fit perfectly with that.
Also a note about HTPC's, the
vast majority of people doing them aren't playing heavy games on them nor are overclocking nor care about "performance". HTPC's are primary about aesthetics and noise control because the environment they exist in, the living room / entertainment / media room, is an environment meant to entertain guests or escape reality. Nothing breaks immersion more when your watching a film and hear your HTPC's fans spinning loudly to cool the overclocked components, or when your guests are sitting in the room having beers and they comment on why there is a loud whining sound in the background.
The 1070 seems extremely overkill in a HTPC, something like a 1050Ti would be more then enough. Hell my HTPC is using the AMD A8-7650K with DDR3-2133 and it's great for what its meant to do. High end gaming is done in the computer room where my beast lives, not in the media room.
Here is what I'm currently using
https://www.newegg.com/Product/Product.aspx?Item=9SIA2F84D68845
This is their newer version, extremely small but looks great.
https://www.newegg.com/Product/Product.aspx?Item=N82E16811108485&cm_re=Chopin-_-11-108-485-_-Product
No way in hell your getting a dGPU into that case so definitely not a "gaming PC".