Buff or Rework "Power of Purpose" Keystone

The keystone "Power of Purpose" from the "Militant Faith" timeless jewel is just not good. The amount of mana investment you need, which can't be used for any archmage builds, is just too much for the amount of armor you actually get from the keystone.

I recommend the keystone converts 80% mana into quadruple that amount of armor (instead of the double). That would allow it to be used in Modern POE with interesting builds.

Otherwise the keystone needs to be reworked, as it stands it is incompatible with any build.

But thats just my suggestion, thanks for reading!