I know Diego Velázquez (1599-1660) is a really famous, top 500 painter and all, but I think he might be even more famous if he hadn't worked for such an ugly royal family. Consider the portrait of Philip IV above, done in 1632. It's ridiculous. The man is ugly, his mustache is an atrocity, his clothes are absurd. Who wants to look at it?
Or this sad infanta. What happened to her hair?
Velázquez was not any luckier in the other important people of the realm; here is Spain's chief minister for much of this period, the Count-Duke Olivares. A face only a mother could love, if indeed she could love it. He was hugely fat, too.
Velázquez did what he could for Olivares, making him look almost heroic by placing him on this Clydesdale of a horse.
But think what he could have done with better material. Like here, in this marvelous portrait of his handsome assistant, Juan Pareja.
Or this face of Mary, from the Adoration of the Magi.
He managed to make Pope Innocent X look formidable, if not exactly Christlike.
But he had to spend most of his time painting Hapsburgs, and a result his biggest fans tend to be people with a thing for the grotesque. The only person I know who really loves Las Meninas (above, 1656) thinks the dwarf is the best part.