Well, the first option sounds really cool, but the third option also really sounds interesting to me as it could have a really good atmosphere - you are just stranded on this huge, seemingly neverending mountain and your only option is to go forward. But at the end, you should do what you feel most comfortable with.
Either way, I will definitely be looking forward to it as the climbing mechanics were really fun. Have fun and good luck!
Definitely the first option, there are so many cool things that could be done with it, some of which I mentioned in my reply had was timed events in the world where some structures are only avaliable to access at the right time and place, with information spread around in the world that tells you where and when it happens, so you might backtrack to a tower you went to very early on because something floating gets real close to it at a certain time, which you only learned about long after doing the tower.
