I was wondering a lot of ask revolve around MC's eventual death, even if the story pointing that they're basically no longer will die of old age (nobody but few people know this), so yes my ask would be like everyone else, after the death of Lukyan, all children grow up, eventually MC turn to grandmother and become great grandmother, if that was me I think I would fake my own death and use elaborate trick to leave the empire knowing I did my best to ensure this empire last for thousand years to come, I mean world is not only the Empire, there is land waiting to be explored, place to visit, seas to sail and mountain to climb, instead of being withdrawn how about MC's eventually get over it, I mean time heal mourning soul, the memories still there but time for mopping around is over, use glamour, fake own death and go beyond the journey's end (taking cue from Frieren).
I think faking your own death to move on and see more of the world is a valid option. Although, I do think depending on how much time passed it wouldn't be necessary and MC could just leave. In any case, I don't blame any MC's that want to leave the empire and explore the world after the plot of the book is over.