Damedus explains the differences between these two custom firmwares:
NCCE is using aroma to give it a visual appeal on how to install extra apps and features. As for game libraries we used the same libs that skelton facilitated me, on top of 1.3 that has the dpad fixes. Dont know if skelrom added any more changes, but i used a tweaking tool(From Jellybam) in the ncce environment to speed things abit, I had some bootloops, start over until I found the tweaks that wouldn't give a negative impact to the rom. we also removed the phone issue that showed the battery being used to get network signal and removed the airplane mode. Vektor did some battery changes and wallpaper changes and added the skelton libs into the firmware, and from there its been getting aroma to work. so as you see its up to you which to use and as for the features you can easily use aroma patch to install any apps u want from our optional pack its not restricted to NCCE, also its all open source so feel free to modify as you like, you can use skeltons CMW too to make a nandroid and return back in case you mess something up.