Still didn't follow the -2 mito.
Also, over-all and more related to the whole thread : From my experience with Mito Guards (that is somewhat large), Heals are better a lot of the time.
Also, you can use Adrenaline and Heals with un-upgraded Mercs -- 3 is one of the magic numbers for adrenaline after all.
Maybe a few less empathic bonds and more heals is in order.