That and then I think the next movie I recall with him was Push. After seeing him play those two parts I just had a hard time picturing him as CAP.
I actually liked Push, but as far as Human Torch goes, at that time, how known was he? I thought he embodied Johnny pretty well, actually, but to me, he was born to play Captain America, and some credit should go to the casting directors for those movies. I don't think I had the same issues as you picturing him as Cap. The first movie did a great job showing his origin story -- in fact, I'd suggest that the first Captain America movie was the best origin story in the MCU. Not the best movie (for example, Iron Man was a better MOVIE), but definitely the best origin story.
Although to be fair, if you think about it, there aren't many true origin stories in the MCU. Thor was already established as Thor when we first saw him, and technically the MCU bypassed Banner's origin as the Hulk.