I'm running nova and have never had an issue with it. Are you sure it's nova and not one of the other "100" apps you have installed? If you've tried all kinds of launchers, and you're getting the same issue, then that to me says it's another app.
Have you tried wiping the phone clean (after backing up the data with say Titanium Backup) and just installing the launcher and seeing how the performance is then? I would then start installing apps one by one to see if/when it gets sluggish for you.
Or you can freeze/disable the apps rather than uninstalling or wiping clean to see when the sluggishness goes away.
Another question is has it always been sluggish? What do you mean by sluggish?
Definitely having 100 apps loaded and depending on what type of apps they are, could cause sluggishness as well, especially if they load up by themselves.
What exactly are these apps? What are their purposes? There are way too many variables with what you've described to be able to pin-point it down to the launcher itself.
Sent from my Droid RAZR MAXX HD under an Eclipse.