Most of the villains in the MCU are very flat and only have one goal; power. DCU’s Man of Steel’s villain was General Zod who actually had some very relatable motivations. He wasn’t after power, but after a way to save his race. It’s kind of telling where a DCU’s standard film has a more compelling villain than most of the MCU’s villains. Though that being said, it just goes to show how charming the protagonists are in the MCU because they are the ones who really carry the film. 

There are films like The Winter Soldier that makes it work since the story revolves around Steve finding his long dead friend, while HYDRA is taking advantage of the world’s desire for security to squeeze themselves into power. The villains themselves aren’t compelling, but the means of which they are trying to get power is an excellent cautionary tale.

Then you have a villain like Loki, who becomes an antihero, so he has an ark.

Since I have seen Infinity Wars yet, And this time marvel has come up the most powerful villain told by critics  "Thanos" who is quite the compelling and menacing villain.