Best screen protector is the "white stone dome" very expensive but very worth it. Not to many cases will work with screen protector check youtube like gravx or u droid mania. I have the spigen rugged armor and it fits perfect almost too perfect
Sensativity can be changed by simply using bixby and saying sensativity settings..if you are still having issues after adjustment it could be one or more factor. Type of gloves, type of screen protector, screen protector not on fully. My friends use the fingerless type of gloves when cruising. Hope this helps.