Set up tubeless with the XR4s and fitted it all,weight saving = 0g, probably down to the more substantial tyres. The sidewalls are so much thicker than the Nobby Nics.
Go for it. The Pike will be a massive improvement over the Float evo.
Don't worry about the cable rub, it's a mountain bike so it's not going to stay in showroom condition for ling if you use it.