Will Marvel's next solo hero movie introduce another one of Thanos' infinity stones? I think that he'll obviously make an appearance in avengers: infinity wars because INFINITY! It's probably got an infinity stone.
Balder, Thor & Loki's other brother whose titles included "The Gentle" and "The Protector", knows how to deal with both Loki's mischief and Thor's temper. He would have been an interesting inclusion in the MCU. <---- yeah, until Loki kills him.