I was wondering which Captain America villain is better in your opinion.

To me, I find the contrast between Red Skull and Baron Zemo to be quite interesting, and in some ways each is better at a different kind of story.

Red Skull is the embodiment of the Nazi ideology, and as such, his characterization is that he's pure evil. He's made to stand against Captain America's virtuous character and American spirit by being the exact opposite of that. Red Skull is also a major player in HYDRA, the big Nazi remnant organization of the MU. In short, Red Skull is made to be a total villain, and you could argue that's for the best.

Baron Zemo is much more nuanced in comparison. As a child, Helmut was raised by Heinrich to believe in Nazism, but eventually abandoned it. He's his own thing in terms of morals. He's still a villain, but he has genuine tragedy in his life, and you can get the sense that if things went just a little differently, he would've been a better man. Baron Zemo has occasionally worked with HYDRA in a matter of shared interests, but really, he's more likely to be separate, often leading the Masters of Evil.

The contrast is that Red Skull is meant to be a full villain, and you could get lot of mileage out of someone that heartless. On the other hand, Baron Zemo is allowed to have depth, be more in a gray area, and be someone you can sympathize with while still rooting against. As a result, they work in different kinds of stories. Red Skull may be Captain America's iconic nemesis, but you absolutely could not have made Siege with him and not Zemo. Likewise, Zemo was the lynchpin of the original Thunderbolts, a story only he could've done.

I think in general, Red Skull works better as a villain to a lone Captain America, while Baron Zemo works better as a villain to Captain America in team stories (ie Avengers vs. Masters of Evil). Red Skull is best for black and white morality stories, Baron Zemo allows for more gray in between them.

Overall, which do you prefer and why?