The average AA for acceptance across all optometry schools is approximately a 320. This is just an average though – you can certainly get accepted with lower OAT scores depending on the strength of the rest of your application and where you apply.
Many schools also have cutoff minimum OAT scores. Each school has a different cutoff, and some have no cutoff.
It is generally favorable to show consistency across all OAT subjects (demonstrating that you are well-rounded) rather than a very high OAT score in one OAT subject offset by a very low OAT score in another.