-tetsuo-
Unlimited Capacity
The side content (aside from the creature tracking one and the murders, until the end) all consist of what are essentially challenge maps/AR challenges, just contextualized with flavor dialogue within the main game.
And it's all optional
Yea I never really did any of the challenge map stuff. It kinda suck that they have the AR challenge stuff, and the Most Wanted ends up being just more challenge map stuff. I will most likely just do the main story and move on.