All it does is give health and a little bit of sustainability. If you want armor/mr, you have to wait 10 minutes into the game which by then, the game is already decided. Also, you have to choose between whether or not you want to have a lot of health or a lot of armor/mr. Why can't we build both. All you're doing is forcing players to build damage and making tanks feel less tanky. Assassins and ADCs can build nothing but lethality, armor pen, and BOTRK to deal with tanks. Mages have two items that just allow them to shred tanks. There's a lack of MR items. The resolve tree should've made for it.
Why does the Precision tree get the Tenacity rune and not Resolve? Why do you have to wait 10 minutes to get armor and MR stats from your runes when ranged champions and champions that do a lot of early damage can just dominate you and deny you cs in the first 10 minutes due to your squishiness? Why is second wind, bone plating, and conditioning in the same row when you can easily swap unflinching and shield ash for those two?
For champs that thrive off health, wouldn't it be healthier to just nerf their health percentage synergy?