A ryzen 3 2200g and a nice asrock motherboard would make room for it, without affecting the performance much at all.
Good build, but for the price i'd try and fit in a 1060.
I know i'm late to the part... but guys calm down with the cable management stuff. who cares if your pc is 62 degrees Celsius vs 60. Lets be nice and tell this guy how awesome his build is. I would personally clean it up... but i'm just petty like that. I Think its funny and i'm glad you have such an amazing build.