I like the case choice, it's not small by all means lol so make sure that fits your definition of "slim case".
For the mobo, not sure about that MSI, why the 970 NB? You can get the 990FXA-GD80 V2 for less and it's 990FX. Otherwise for an extra $40 you can get the ROG Crosshair V Formula-Z which is a very solid board that will get you higher overclock.
Because it's $100s less and a full atx board.