Bond of stone change: Convert 6% of dmg taken by nearest ally to heal you, remove flat dmg reduction
Currently: Grants 4% reduced damage. In addition to that, 6% of the damage that allied champions would take from enemy champions is dealt to you instead (cannot reduce you below 5% health).
Changed: Converts 6% of damage taken by nearest ally to healing on you
It still grants damage reduction to allies but now sustains instead of damage redirection and damage reduction
This would be an especially good change for Supports who lack innate sustain, prefer consistent power compared to windows of power, or can not efficiently utilize the other Resolve keystones
P.s. If slightly underpowered could keep 2-3% damage reduction :P