Your airflow will be fine if you add 1 or 2 fans, no need for more!
Also you can save that money for a R9 380 which is a much better card than the GTX 950 or 960 and only costs you a bit more
EDIT: DO NOT GET THE ISKU I HAVE IT AND THE DRIVERS ARE VERY FAULTY
SAME WITH YOUR MOUSE
Whats wrong with drivers? is it a Roccat issue?
They do not work. You install them and they can't find your device I have one for Windows 10 and it took me ages to finally find a previous version to change the color of the led to white