Pavarotti has a specific figure, fantastic voice, but in a couple of minutes you forget it's him. Through the character of singing, it's no more Luciano. I wish young artists would follow that. Forget about yourself on stage. Follow the characterisation of your heroes.
Every villain is a hero, of course.
You can show him as hero as well, otherwise you can lose him in between. If a tree is ordinary in a forest, you wouldn't notice it, and it's the same with villains, whose figure should be in clear profile. It is also a question of balance, of character, but also in broader historical and political perspectives. If we're talking about Prince Igor, he is a historical figure and a hero. Even with his unfortunate things, he is the hero the survivor and leader of the whole Russian nation.