I'm not sure if what you describe is really an inability to get the big picture or the lack of available information to really base decisions on.
For me it's hard to make that kind of decisions because other people can't plan well and their estimates are notoriously wrong and forget to take into account a lot of things.
But what I'm really good at it seeing the bigger picture in the sense of knowing the interdependences between things. If I see a requirement I don't just follow it point by point. I think about what how it fits into the whole and where things can go wrong and ask if people have considered that. (90% of time the answer is no)
So I consider seeing the big picture and the details my strength, but like you I struggle to plan ahead long-term or estimate things because I don't feel confident with the amount of information available to make such guesses.