Honestly I hope the vast majority of these characters get retired come the next game. They all had their time in the spotlight, time to wrap them up and get a whole new cast of characters. Probably better to leave most of them be now anyway.
Well, with the exception of Zevran I guess, though I'd say him not appearing is the best thing that could have happened for him. As a result he's the only DA:O LI who's actually physically still with the Warden, and thus the only LI that's actually helping them on the Calling cure thing. Also the only Origins romance that doesn't have something potentially happen to them that could...complicate things. (Alistair...well, dying, Morrigan drinking from the Well, Leliana becoming Divine...)
Hmm.
I think that's to be expected considering that the setting for the next game is more likely being set in unexplored regions. However, I think a lot of people would be curious about what happen to their previous games' PCs because they're still attached to them after all these years (I am not talking about new players, of course). Killing them off-screen is a relatively bad cop-out plan by Bioware, if that happens (unless the next game is being set 10-20 years after Inquisition/the Last Flight, so time-skip plot device is being used again).
A little bit spoiler-y, but I think Lady M. would still play a significant role in the next game. She had been missing since Witch Hunt, and only to be seen again at the Winter Palace. Compared to Leliana who appeared in DA 2 and its DLCs as well as two novels, or Alistair who has his own spin-off comics, I think that's... fair. Zevran would only get the short end of the stick, I suppose.
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Man, I am not interested in participating in this heat because I am more of a live-and-let-live kind of guy when it comes to our own personal World State, but let me preach.
DivineVivienne4Lyfe. #jailallthemages #allhailtemplars #mageforthesunburstthrone #mylifeforvivienne