Well, we know how this might confuse you - what does Scott Lang has to do with the Human Torch? Nothing, because this is a metaphorical torch, which actually means that an older generation of superheroes will make way for a younger one.
And this was known even before the first trailer arrived, since Ant-Man is actually the last movie of the Phase II and the first new superhero to get a solo film.
And, as Kevin Feige said, this will be the first film in which this metaphorical torch will appear - mentor Hank Pym will initiate the novice Scott Lang into what it means to be a superhero.
A villain for Scott Lang
The villain of Ant-Man will be Darren Cross, who will later on become Yellowjacket (this is the MCU, so Yellowjacket isn't an alias of Ant-Man). Darren Cross (played by Corey Stoll) was a child prodigy which was taken under Pym's protective wing.
Although he bases his research only on belief, he two discovers the Pym particles and creates his own suit. However, unlike the suit Scott Lang will wear, Darren's will enable him to fly - but, at the same time, Darren will turn into a real psychopathic (which is quite the drawback).
Hope Van Dyne
As previously said in here, Ant-Man will also be a movie about the father/daughter relationship - however, Scott Lang isn't the only one to try to prove himself in the face of his daughter. Hope Van Dyne's relationship with Hank Pym is a very cold one - actually, when the movie starts, years would have passed since they last talked.
Furthermore, their relationship is even more shaken because Hope Van Dyne works (for the better part of the movie, at least) with Darren Cross/Yellowjacket.
The trailer
The trailer, which can be seen here, proved to be even more successful than the one of the Guardians of the Galaxy, with 29 million views. And if we recall correctly, the Guardians made quite a few bucks at the box-office"¦ So yeah, the first trailer featuring Scott Lang might have been a bit dull, but the fans were still excited to see him!