Cable Management.

wut....? You can see the cooler with the tubes in the picture, as well as being able to see my sig saying I have an "h100i". Yes, it does.

Ah... my bad. Going back to your improvement comment, it really depends on personal preference. Every change you make now will be minor changes.

>wants to improve cable management
>literally no cables in sight

nice PC

I have never actually fucked with sleeved ones before. But, should I not be able to get that fan on the left out, without taking mobo out I plan on going to a 750D, most likely.

But tell me, do I HAVE to buy sleeved cables that are made specifically for my supernova?

wat? there's a fairly decent amount showing.

I'm really hoping I can't, so I can give the wife a reason for me using my money on things hue.

I think any cables should work on any PSU, but don't take my word for it. I wouldn't take the chance to try.
I can also see that your PSU is semi-modular, so you can't really change out the really necessary cables.

But your cable management looks pretty good as it is, don't think you can make it any better without buying a new case. NZXT doesn't have the best cases for cable management.

If you want a real neat-looking PC that is worth bragging about, you might want to get a Corsair Carabide Air case. They have the PSU in the back with plenty of space for the cables. Which means you won't have to show your ugly PSU and all the cables hanging around. And if you really want sleeved cables for everything, get a Corsair PSU that is fully modular and buy with a set of nice sleeved cables.
But this is only if you have the spare money. Your PC looks pretty neat as it is, with those LED lights and a side panel with window it should look good without any upgrade.