IMPORTANT EDIT: I just discovered an AI issue with Vampirist Matrix. The Coordinate Input state doesn't go away like it's supposed to after firing. I've got to head out soon, but when I get back to my computer I'll have a patch released for this posthaste.
I'll make sure those typos (and the invisible obstructions from the last post) are dealt with by the next patch.
Healing Boosts are effectively a "weakness" to healing. That said, the Omega Wreath will make Tonics do more on temporary allies.
I'm not sure whether to apply Tonic Boosts to Treat or not, as while it's technically not a Tonic, it runs on the same principle.
In the Red Cap Rematch, the main offensive threat is Red Cap, rather than Rauthaz; the only damaging attack Rauthaz can do requires direct input from Red Cap to start up. If Garett has trouble staying up, there's no Bounce Guard for Wind attacks, so he can always cast Twister to interrupt Red Cap and buy Brill some time to throw down more support. Thunder Resistance will help keep Red Cap's Tazer Shot in check, while Regen Formulas and Echo Tonics can be a lifesaver. Red Cap doesn't have any resistance to Ice either, and there's no Bounce Guard for Ice, so cooling him down with a Snow Bottle can help keep his damage output in check.
Boosting Garett's Attack (whether via a Power Booster or with Boost Attack) will make Electron spells stronger, but it'll also be great for his Bright Arrows spell- and when Bounce Guard W isn't up, landing a strong Soften on the Water-weak Rauthaz will make Bright Arrows (and a Rainfall Retort if Brill gets lucky with the random targets) extremely effective (EDIT: under the right conditions). A Heavy Grav Formula will also wipe out a generous chunk of Rauthaz's HP.
EDIT: I forgot Bounce Guard counts as a Block! This is a good time to use Guard Down- and since it's a Block, Shieldshocker potions are really going to come in clutch if it's not Bounce Guard T.