And what big picture is there other then to make the best movie possible? That is a problem I have with the MCU. It is sprinkled with great moments, fun, and a fair few very good films (heck I even find some stuff to like about IM2). But they haven't made a great movie yet imo. And part of me thinks it is down to the production line of films and perhaps a bit too much interference, in the need to build to a goal beyond each individual film.
It is easy to line the movies up in a general way, and really that is all that is necessary imo. And from what I have seen from IM3 and what little we know about the other pre-A2 films, I think they might be doing that and that great film may come in phase 2.