I know there are probably a million threads on armor and how terrible things are now with the proposed changes but I have my own thoughts on what could possibly be a solution.
First the issue. Armor has been removed and replaced with health. Does this therefore not now mean that health is going to be the go to stat roll for all gear. Removing one evil to only be replaced with another slightly different one? To be competitive going forward and to do the most challenging content, you are going to need as much as possible and therefore choose this over any other option.
My suggestion is this. Vastly increase the value of the armor you get natively on gear so that mitigation is increased to a reasonable amount. It doesn't need to be near the old caps of 75% but I think between 50 and 60 wouldn't be too bad. This would then truly give players an option on what to choose for their builds to maximise their potential. Players who wanted to tank could add health or resist all, skill based builds could add more skill power and so forth.
I think it would really allow a true choice on what works best for what you are trying to achieve, rather than being "i need this skill because i'll be useless without it" which i believe we are heading with health.