| GM Rednal |
At 3rd level, 19 AC is a good, viable number, while 24 is basically min-maxed and hitting diminishing returns. ...Of course, those numbers are for PLAYERS, not NPC enemies. Any given gestalt character is probably 1-2 CR ahead (at least), so let's say the enemy is something like a CR 5 opponent. At CR 5, a good armor class for an enemy is 18.
So... yeah, I'd say it's too high. Maybe up it to 20 if you want him to be a little tougher, but not all the way.