Insulation help for my garage with pics

Yeah the door isnt done yet, but I planned on tuck-tape on the seams. The garage is only 500 sq ft, so I use up every sq ft I gots!!
Don, I know the boards need more support. Are you saying to "silverboard" on the angled boards?? If so, I should still drill holes in the soffit though right so the roof can "breathe"

Thanks!!