Warmog's threshold should look at resistances as well as health

The threshold was reduced in 7.9 because:

Pulling health out of our tank items left Warmog’s Armor feeling a bit inaccessible.

It was increased in 8.5 because:

The Warmog's Heart passive is currently forcing this passivity too early in the game, and specifically at too low of an investment. We want champions to be able to opt into resisting poke patterns, but it should take more of a durability investment than just Warmog's Armor to do so.

The health threshold makes this not just a tank item, but a health tank item. You need to specifically acquire health, not just "tank items." Your "durability investment" needs to be health items. Why should items like Stoneplate, or even intermediate items like Chain Vest, not be considered an investment into tanky items that increase your durability? Why should Cho reach the threshold sooner with his ult, but not Garen with his W (I'm still mad that mechanic has a stack limit, unlike those of other stacking champs, but whatever)? Hybrid items like Cleaver count towards the threshold, but another hybrid item like Veil doesn't?

Give armor and MR an appropriate weight for their gold cost and item budget, and then include them in the Warmog's activation threshold. The threshold can then be adjusted for actual durability rather than just health values.

N.B.: I am assuming that Warmog's is a healthy item rather than being kept intentionally weak to prevent people from using it and messing up games, like old Urgot.