Gau: Automatic Rage Learning

So, I don't know much about battle events, and this request might be a bit of a doozy, but here goes.

Thus far with Gau, I've changed his commands to Fight, Rage, Magic, Item (thus I also had to neuter his ridiculous offensive stats & allow him to equip weapons). I've eliminated the need for him to Leap at all, and started him with his full rage list. (I've never had a problem with the idea of fighting a million battles to level up, but a million more for his rage list... ugh!)

The main issue I have with this is that it gives him access to some pretty potent stuff pretty early. What I'd like to do is change things such that whenever the party first encounters a monster that could appear on his rage list, Gau learns the rage immediately instead of just the monster being placed on the Veldt list. Of course, I still want the monsters to appear on the Veldt as normal, but I'd like to skip the middle man .

I'm betting this would take a lot of work, and I'm fine with this, but I'm not sure where to begin!

EDIT: P.S. That means Guards and Lobos and Pterodons (etc.) pop onto his Rage list at the very beginning before Gau is even defined, all the way to the end.