The folks above said it all.
Pros of CM:
- with the monster of a processor with 4 cores running @ 2.3 gHz (in your Exynos case, 4 @ 1,9 gHz and 4 @ 1,3 gHz), s**tload of RAM and so on, the CM is "fast as hell", which is an understatement. On any TouchWiz based ROM the usable limit is 2740 MB, and on boot around 1-1,2 GB are already busy with Samsung's bloat. On CM the max is 2840, and on boot the already busy memory is not a lot, I've managed to cut it down to around 600 MB, which leaves... 2.2 GB free.
- with CM, you're always with the latest possible base of Android.
- with CM, you get circa 26 GB of free storage, TW ROMs give you 22 max.
Long story short, if you intend to use the Note for some awfully heavy duty processing and you want to eke out every shred of resources it has, CM (or for that matter, any AOSP based ROM) is the way to go.
Cons of CM:
- it takes many nightly updates before you get a good really stable version, you have no idea what bugs might be within a nightly.
- the Note is named that way for a reason. xD That thing has a Wacom digitizer which allows the use of that nifty S-Pen and it's abilities, also, I shamefully must admit, it's fun as hell to use.
However, Samsung are being businessmen in this regard, some might go as far as calling them d**ks, because the SDK for that pen is not open source, therefore, devs are not able to put software for it into any AOSP ROM.
- yes, the Camera. Samsung's camera app also is not open source, and you take noticeably better photos with it than with the AOSP camera.
Summary: being a sysadmin, you're able to control your server with an Android device, I'm not sure if that is loading the phone a lot or not, but if it does, and you use that Note for processing more than casual use (photos, doodling and drawing, etc.), CM is what you probably need.
Otherwise, TW based ROM would be better.
P.S. The best phone for heavy duty processing right now would be the OnePlus One, it has the Note's 3 gigs of ram, 4 cores running at 2,5 gHz, and CM is it's STOCK firmware.