So what if Warlord's was just a straight up sustain Keystone?
As in, 'You heal for (percentage) of the damage you deal to champions'.
That's it.
No crit nonsense. No bonus stats. Just a straight up sustain mastery. Because it strikes me as strange that the tree dedicated to DPS/Sustain only offers capstone sustain to champions who build crit.
Or any wave clearing mage with mana item & blue. Would probably be retardedly op and picked just as much as it is right now.