Endurance Charge Generation Is Lackluster

Lvl 71. So far, I've only found 2 sources of Endurance charges from skills:
A timed block
And 20% chance on Armor Break support gem.

This limits endurance charge generation to a very low amount of possible builds. Not to mention extremely limited for anything not Warrior.
My current Avatar of Fire build has no need for armor break so that's one out the window, and all I got left is to spend time trying to timeblock things on my 2nd weapon set, which against large groups is okay but against bosses not really. There's large windows of time where bosses don't throw blockable attacks (the campaign fire guy at the top of Temple of Kopec comes to mind).
Haven't looked into uniques yet but there should be a somewhat more reliable way of charge generation built-in the Strength archetype.

thank you for reading

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