Got about 50% of the map done, got the grappling hook,
spoiler (click to show/hide)
hit a few of the 'glitched' zones
and am now not sure where to go... made it really far to the top of the map but hit a dead end. So now I'm backtracking to the first few areas of the game. The map is really huge, and there seems to be a ton of shit to collect. Game also is quite challenging... save points are spaced far enough apart but not ridiculously far, and enemies hit hard.