Michael Korvac is not known as a Thor villain but rather a Guardians of the Galaxy and Avengers foe. His “Korvac Saga” in the 1970s which saw the god like being take on both the Avengers and Guardians, is considered one of the best story arches in Marvel Comics history.
Born in the 29th century Korvac clashed with the original Guardians of the Galaxy and also a time-traveling Thor. After his defeat, he traveled to a space station that belonged to the planet-killing being known as Galactus. Here he downloaded knowledge and technology so advanced that it gave him godlike powers. His new abilities enabled him to believe that he could use his powers to reshape the universe into a utopia.
Korvac was so powerful that he was able to take both the Avengers and Guardians without breaking a sweat. He would have succeeded in destroying them to had a woman he had fallen in love with, Carina, not started to doubt his plan.
Bale would certainly make a good Korvac. He would give the character great depth, strength and fear. However, he just seems like too big of a character to be used in a solo hero film, even if it is Thor. I would think he would be used as a mid-level Avengers villain, similar to Ultron in the second Avengers film. My dream scenario would be that Marvel uses him as a tune-up for earth’s Mightiest Heros before they face off against someone like Tyrant or even Galactus.