Ability to fight in multiple quests

What's the point of having an entire roster of champs if at a given time, I can only use a max of like 16 (3 AQ+ 8 AW+5 quest). Like with the mole Man event, which costed zero energy, I would have liked to be able to play both the monthly EQ and the side quest simultaneously. So if I run out of energy while in the monthly EQ, I can hop over and play the side quest.
What are your thoughts?
What are your thoughts?
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