It's not supposed to be easy to get "all" the content (as much as you can get in one playthrough anyway). It's just meant to be possible. This game is designed around the concept of NG+, where getting everything becomes much easier. Someone playing through this game only once will miss content no matter if he's following a walkthrough or not. This is by design, and it is part of the game's story. It will make sense, but I can't tell you why at this point in time. Suffice to say, nobody needs to stress out over the time limit. It won't be a problem in the final game.
Aside from that, everything is going to get a balance pass when all the content is in place. At some point, probably once the story is finished, but perhaps even at the beginning of the endgame, I will invalidate all saves and rebalance the entire game. This is going to cause havoc with walkthroughs but will also be the final time that is going to happen in any significant way, so it's not all bad. The time needed to accomplish various tasks in the story will likely be adjusted as part of this process, which means some things might take fewer actions while others might take more. The former is more likely than the latter. In particular, the requirements for reaching various parts of the story, in terms of abilities, will likely be heavily modified.
While reports about how long it takes to get through the game right now are useful as I prepare for this balance pass, those same reports shouldn't be used as an exact guide to how long it will actually take to get through the final game.
