It was so much easier when I was an eagle.
So, as always, I've started off by ignoring the story and trying to scale all the viewpoints in order to unlock the map. What is quite interesting, though, is that I have a much lower drive to get the rest of the side missions completed when I don't have the achievements or trophies to chase. I'm happy to see the pages disappear into the distance, not chasing them like those awful dynamic orbs in Crackdown 2. I'm far more likely to head for the exclamation mark to continue the story. This is shaking off years of videogame training, where sidequests may have been optional but they always made progression easier; in Assassin's Creed the benefits you get are marginal at best.
But it's still a bit overwhelming.