Yeah, id love to be able to have conversations with the endings I chose with these NPCS. id really like to encounter Rolan and his sibs, or Zevlor again. And, again, in regards to map creation, they could limit to visiting only the area they are at. Like visiting their homes or whatnot. Doesnt have to be an entire area of Waterdeep ect...
Id like to be able to mess around with a home, with the character I romanced and the ending I chose. For ex, with Gale and the tower of waterdeep, you could purchase paintings for it, or sculptures. For Astarion, maybe you have a home in the underdark you can decorate with him, or add things to the palace for Ascended.
Something small thats customizable to cement that you won an ending and youre moving on with your life with the friends and lover you have. You can reload in explore the ending you chose, the characters you love, and the home you made with your lover you chose.
It would be a nice touch is all.