1) bumpers, winch, rock rails, skids, fenders will all add weight. Therefore the 4,4.5” lift will more than likely be less than that.
4) nice rig.
IIRC the quality companies factor in a JKU with bumpers skids and winch in their lift heights. I know at least RK does. I would look into it if you're planning on it being less than 4/4.5" after the armor.