I personally use the Jaybird X3's they really have great audio and are really comfortable for me.
Though they aren't the cheapest option out there though if you do look around I am sure you can get them for under $100 and to me they are good value for that price.
Here's a decent resource...
I personally use the MSI 970 Gaming and it works like a dream for me, I personally dont think motherboard and ram are super important. I usually just stick with a good brand like msi and go from there
I actually use the xiaomi air 13 for playing LoL and cs go and its runs perfectly well, though if you are wanting to play more taxing games it wont work as it only has 1 gd of dedicated video ram
some people say u need to test ram for long periods like 24 hours + plus but I personally feel thats overkill and I usually only do it for 1-2hours max
I mean mostly depends on the game/s you are playing, if you are playing all the latest releases and want max setting the 1080 would be the choice though if you are just wanting to play game like cs-go and league of legends on max then the 1070 would be more that sufficient I think
Its hard to tell exactly when it will be over, a similar thing happened when the bitcoin craze first happened and initially the formula that the graphics cards are used to break down was quite easy though now its vastly more complex and its simply not worth mining with a card anymore for...