Endgame spoilers ahead!
Since Tony Stark made his sacrifice, someone has to take up the mantle of Iron Man at some point, right?
This is why I want to see Riri Williams in the Mcu, and she is also Ironheart aswell, which is neato burrito.
I also want to see the Spider-verse event be adapted to the MCU, we could get introduced to Otto Octavius as the Superior Spider man, we could also get Silk, Miles Morales, and so much more.
Lastly, I want to see Amadeus Cho. Amadeus has appeared in 2008's "The Incredible Hulk" and hasn't appeared since then, we also saw his mother in Age of Ultron, so it could be possible that Amadeus could appear again, either in human form or as the Totally Awesome Hulk.
But those are just my thoughts. Which characters do you want to see in the MCU?