Looking at 40c 7PS 170wpf using +3 values against 5 shield (40% final damage reduction and assuming shield damage works like armor)
Hand Pavise: 418hp 28armor: ~35 damage per hit reduced to 21, 20 hits final (although barely under 20)
Knightly heater: 285hp 39 armor: ~27 damage per hit reduced to ~16, 18 hits final
Knightly kite: 323hp 29 armor: ~34 damage per hit reduced to ~20, 17 hits final (although just barely over 16)
Worst case may have a difference of 5-6 hits between knightly kite and hand pavise, but it will still remain somewhat close to the knightly heater overall.
Shields may not work 100% like armor, but the point I am trying to make is that looming to +3 gives a smaller % advantage with the +53hp and +4 armor. This makes the knightly kite both light and durable. Knightly heater would also be much more effective against lower damage attacks and ranged. Hand pavise is a little strong, but it is heavier.
It's a little on the weak side overall, but it pays more for its light weight. It could live with a few points more armor (or nerfing the elite cav shield)