I just took another listen and I think I hear what Gavin is saying, but I have a simpler solution. In your verses you change the chord progression for lines 3-4. If you save that progression for lines 5-6 and just repeat 1-2/3-4, I think your vocals will naturally build into the chorus better. No need for extra lines or chords, keep it simple and treat lines 5-6 like a lift smile