I thought an interesting alt universe could be one where Captain America rescues a young Erik Lensherr and the boy becomes Bucky, the magnetic kid. His control over his power goes haywire or isn't strong enough to take down the plane and Steve, wanting to save the young boy's life, pushes him off and disables the bomb on the plane, Erik barely surviving as he floats out of the water upon regaining consciousness but can't find his hero. Cue the government having Erik take upon the mantle of Captain America and living up to his name, controversy abound as he's the first public mutant. I figure he meets professor Xavier while hunting down HYDRA and Xavier helps him find the frozen captain. A tearful reunion happens and things will never be the same