The whole premise of this thread is somewhat puzzling. Lindsey has always done ballads. Even such songs as Soul Drifter and Oh Diane are ballads. THE GOS leaked songs included a bunch of ballads. So whether he will do ballads for the new album is moot.
I think he should invite Carlos Santana to do a duet with him on a ballad. Perhaps they could retread "To All the Girls I've Loved Before."