A lot of good points made in the comments. She's her own woman & doesn't see Lucius as a romantic interest (yet anyway). I think the author could take it either way tbh.
One GOOD thing that would result from her becoming an empress in her own right would be a gradual change in the way women are viewed in their culture. There are probably other girls like the twins that worship her already. Her subordinates from the war changed their view of her & respect her. Aino's a perfect example of a stubborn jerk who gradually accepted her efforts & accomplishments despite Pauliana being a woman (took almost a decade though). So who knows, her example may bring other talented women out of the woodworks.
I think the author could justify the story either way, as long as it's properly thought out & not rushed.
In the meantime, there's too probably much political scheming going on. Those old bastards need to go.