MCU Phase 4: 10 Things They Must Address (And Not Just Forget About)
5. Alternate Dimensions
On the note of a dimensionally-challenged Gamora, the fact that alternate dimensions exist in the MCU is a pertinent fact that simply cannot be ignored in the future. That Evan Peters appearance better not be the end of it.
Shock cameos aside, it is a fact now that different timelines are a thing in the MCU. This very fact simply has so many potential through lines it would be a crying shame to see it not get used further, whether that's for future Scarlet Witch content or to see Doctor Strange meet alternate Avengers.
On a further point, it could be interesting to see alternate versions of past MCU events. For instance, a timeline where the Chitauri successfully levelled New York, or the nuke hit its target, or where Sokovia actually crashed into the Earth following Ultron's natural disaster fawning. Maybe even one where the heroes completely failed to stop Thanos' snap, but on a more permanent level.
Stories like this are dripping with moral implications and emotional reckoning on a serious level. Imagine Strange or Spider-Man witnessing a devastated NY landscape or post-permanent snap Earth; such a powerful situation, with severe emotional power should Marvel choose to pursue it.