Lang is Ant-Man, Pym created the technology. That's what they are going for in Ant-Man.
Thats what I meant, yeah. Pym can be considered "Ant-Man" in that he created the technology, but not that he uses it as superhero. Like it is in comics just without Hank Pym actually using it, but its pretty much the same.
Also the nature of the changing size is changed. Instead of physics method of using "Pym¨s particles" to change size, it will be some biochemical substance (not sure how they want to pull it out).
Yes, I suppose that either Vision will be JARVIS physical body, or something created from him. Maybe Ultron will destroy Stark's computer net so JARVIS, to be saved, will be moved into body that will be Vision. The options and possibilities are limitless.
Well, the Mind gem may be that gem on the Sceptre, it is even hinted that the Spectre will make some prominence again in Avengers 2. I was quite surprised that von Strucker will be here as well, thought given the nature of Hydra its logical. Thought using the Mind gem to make Ultron alive and sentient... Ultron was always an artificial intelligence. This way he can be truly logical and methodical. But with "mind" he may have emotions which would be his weakness. And from wat I learned of Ultron he is one of the worst enemies of Avengers, especially with that cool head that is scary. Also why would they suspect Mind gem is actually useful? And when Strucker has it, how can he use it on Ultron, who is most likely Stark's creation?