While I didn't get any speed enhancements I definitely noticed that fewer apps are being taken out of memory. Before my apps would reload relatively quickly as a result of Samsung's aggressive memory management. Now, it only happens every now and then. I never viewed Nova Launcher as being memory intensive and I didn't even activate the aggressive desktop/memory mode. But it seems it takes enough memory from the edge to force other apps to close more often. I suppose the s7 is at least prioritizing the launcher over other apps (good) because I never had issues with launcher performance or reloads.
Just curious--when you had Nova installed, was TouchWiz Launcher still showing up in Running Apps, as a cached or background app? If so, can you try disabling TouchWiz? I don't have direct access to an S7, so I'm not sure if this is possible in the first place, but just thought I'd suggest it.
Thanks for keeping this thread updated!