Ended up going with:
MSI B350 PC MATE
AMD Ryzen 5 1600 3.2 GHz 19MB
be quiet! Pure Rock
G.Skill 16GB (2x8GB) DDR4 2400MHz CL15 Flare X
ASUS GeForce GTX 1070 8GB ROG STRIX DC3 OC
For the monitor I went with the Asus ROG Swift PG278QR just because I could get it super cheap ($200+ discount).
So essentially all I'd need to add is a new PSU, though seeing as how my old one was massively over budgeted in my pre built PC (
http://www.coolermaster.com/powersup...ro-gold-1200w/) I feel like it's worth holding on to. As for the case, I do like my current one. It would be a quite big relief not to have to empty out the old one I suppose though, but in the end I feel it's worth it (and hey, I won't have to deal with moving the SSD & HDD).
Btw, in regards to getting a new windows key which is in the end probably what I'm going to go ahead with to not have to bother with contacting windows and whatnot. Will reinstalling a fresh copy of windows wipe my C drive? Both my drives? Or only windows settings? Also, I'm currently on windows 7 so I guess I'll have to get used to windows 10 (is it worth?).