Your temperatures at idle don't really matter much. Those look fine though.
You'll need to play a game or something and see what the temperatures are using software like HWMonitor.
Generally you want under 65 for your CPU and under 70 for your GPU. Or there abouts.
Every week, youll find yourself opening it and fiddling around to manage cables amd whatnot
This is not an advisable habit. More you tinker more likely you are to break something or mess something up, especially if its already working fine. Not to say you shouldn't take a stab at cable management at some time, but every week?
OP, unless the current fan noise level bothers you I'd just leave them.
CPU under 80, GPU under 90
Subtract 10-15 degrees from those and you're right.
OP, what size of monitor do you want and what resolution?
Under stuff like Prime95 and Furmark
I'd want to be nowhere near those temps in any situation really. Especially the processor at 80.
Dont worry about it.
Initially, the mobo will downclock it to 1333 MHz, but just enable one of the Intel XMP presets and you will be golden