Jeanna Anne: is going to see Elizabeth's coronation and scenes from her time as queen.
Blossom: She'll be seeing pretty much the same thing as Buttercup. A life with her sisters, them taking on bad guys and winning.
Gamora: Remembers the first time she realized that she loved Peter and seeing them happy together in the future.
Natasha: will see herself and Clint with a newborn and flashes of the two of them watching their daughter grow up and a happy life in Goodland.
Luke: Not sure about this one but probably the battle of Yavin, blowing up the Death Star, the whole medal ceremony (I'm such a damn sucker for that scene) and how happy they all were.
Oliver: sees Tommy and all the good times they had growing up.
Marty: sees himself as a successful musician/songwriter