2. Young Hank Pym
Rather than exist as another character alongside Paul Rudd and Michael Douglas' Ant-Men, Patrick Wilson could be a younger version of Douglas a young Hank Pym. The film could explore Hank's life as a young man, how he got his powers, and how his experiments led him down the path to creating the artificial intelligence, Ultron. This film would follow The Avengers: Age of Ultron movie so audiences would already be familiar with the character, but some backstory as to how he came to be would be great. It might also mean we get a brief appearance of young Hank Pym in the Avengers sequel to set up Ultron's character. Wilson's taller than Douglas but not by much and with the right camera angles, you wouldn't be able to tell otherwise. Plus this is a character who's known for shrinking and growing his height anyway! As most of the movie would probably focus on the present day Ant-Man, Scott Lang, I'd expect Wilson's part in the movie if he were to play the young Hank Pym to be mostly flashbacks and/or a brief sequence at the outset. But Wilson could definitely be an excellent young Hank Pym.