just super helpful there mate. any real info??
Descriptive titles are better.
"is it possible"
Would have been better as:
"Is it possible to root and only run Nova?"
Then we can see what the thread is about without coming into it.
If you're not getting drain just using touchwiz, it's not going to mean you get massive drain when using a replacement launcher.
Unfortunately touchwiz home does still run when using an alternative launcher (if you go into applications manager > All > Touchwiz home, You will see "Force Stop" is available as an option). If touchwiz is in RAM that doesn't mean it's using power. However, if you have lots of widgets that update on your touchwiz homescreen, it would be worth removing them as they will still be updating so effectively you could have twice the amount of widget updates than necessary.
With root, you can freeze system apps using Titanium backup pro. I wouldn't recommend deleting it though because if you factgory reset you'll have NO launcher and that is no good.
Rooting for thios is overkill though. If Touchwiz homescreens are clear of Widgets, you will not be using any additional juice.
Step 1 - Clear your touchwiz homescreens of all widgets
Step 2 - As already mentioned, install battery monitoring software like GSAM or Better Battery Stats