http://cbs.sportsline.com/nfl/story/8536477
Redwagonskins,
You're right that he can't flash a weapon and point it at someone unless there's a viable claim of self-defense. However, his returning to the scene doesn't necessarily destroy his self-defense claim (if there is one). If he felt threatened and there are facts to back up that claim, he might have a self-defense defense to the charge. Moreover, returning to the scene and hitting someone isn't aggravated assault - it's simple battery (hence the charge of simple battery).
You're also right that he's a total jackass (based on what we now know). But, we have few facts on which to base a judgment about how strong the State's evidence is, what Taylor did, what Taylor was responding to, in what circumstances he brandished a weapon, and in what circumstances he hit someone. Until I get more information about the whole incident, I still reserve final judgment about the situation and Taylor. My preliminary feeling though is that you are right and he's a total jackass.