Question on cast on critical

Hello Exiles,

In the game it says:

Gains 1 Energy per Power of enemies you
Critically Hit with Skills, modified by the percentage of the enemy's Ailment Threshold the Critical Hit will deal.

Does this means, if I reduce the elemental ailments on the monster with "overwhelming presence", I will gain energy faster or more?

Also, does damage affects the energy gain in any way?

Does heralds help with energy gain if herald of ice shocks and herald of thunder freeze?

Thanks in advance for any reply!