Action.
The biggest problem with modern bland villains is having them sit idly by while the story focuses entirely on the heroes. No one is frightened or in awe of a scary-looking dude standing around offscreen. Give him moments to be villainous. Give him his own plot and motivations and supporting cast so that, even if we don't like him, we learn about him and invest in him.
It also helps if you give him a signature moment that puts us in awe or in fear of him. One of my favorite parts of Dragonball Super was when we first see Goku Black facing off with Trunks in the future. Trunks turns super saiyan and drives forward with a punch to the gut to send Black flying backward-- and throughout the attack, with Trunk's fist still in his gut, Black is cackling like it's a joke. It's monstrous and ominous and disturbing and I love it.