But, there are some problems. The Avengers 2 is currently slated for May 1, 2015 (the typical Marvel release date for their major event films) and Ant-Man, which will be directed by , opens nationwide November 4th, 2015.
But here is what I am thinking.
At the end of The Avengers 2 (post-credits) there might be a tease of Ant Man. That is extremely possible because most Marvel movies (post-credits) lead into others, but it could not happen, maybe Phase Two will only have clever humor (see: Iron Man 3 post-credits with Bruce Banner).
That Avengers 2 tease could really boost numbers. After Ant-Man, Marvel will most likely have an Avengers 3. Maybe he could be in that.
Phase Two has already begun with the third installment of Iron Man. The next film in Phase Two is Thor: The Dark World, which released a trailer a few weeks ago. And may have a slight bump because of The Avengers.