Recovery and Damage are not the same thing. Comparing the differential to existing skills is apples and oranges.
Looking at Druid's Resurg on Shield Throw: "Increases your Health, Magicka, and Stamina Recovery by 152 for 10 seconds on return." That 152 is added to your recovery, which is a value in combat that regens every 2 seconds, so the amount is 76 per second. Compare this to Druid's resurg on Mender's Bond: "Restores 74 Magicka and 74 Stamina every 1 second for 5 seconds". On Torchbearer: "Restores 74 Stamina with each sweep."
So, obviously 76 is not 74 but it is close, and the "on return" part may account for the slight difference, basically a round error due to a 0.5/1.0 second (essentially) post use cast time for use of a better phrase.
So is there consistency between the variable regens of the script - yes.
Does it need to match any existing regen in-game? No, why would it?
All values should be based on something standard in the game.
How the dev team calculated the bonuses? Based on what?
For example: Druids' Resurgence gives 152 recovery which is 1.81 times the prismatic enchant while Wayfarer mastery gives 333 bash damage which for 5 seconds only which is twice as short and the value is only 0.66 times from the enchant.
Why should match any other regen? It should not. But it should be based on something. Not thrown randomly. When is recovery or bash damage, weapon damage and so on it is easy to match it to an enchant or mundus stone and this what the devs did so often and we as players are used to that.
Why this is is important? Because otherwise you have some items which brings more value and when you theory craft these items stand out.