What exactly does the Regen stat do? Is it meant to regenerate health? If so, it doesn't seem to be doing anything. My units are the same health, even when taking 0 damage in an encounter and having a Regen of 20+.
I think that Regen, as it is, is perfectly fine. However, I'd recommend adding a tooltip to explain how a unit's stats function, and how Absorb functions. At first, I had thought that Absorb would apply all of the stat modifications, but it only seems to do a percent of the total (presumably tied to the Absorb Rate upgrade?)