Unlike Leonardia, Prince Edward has a good eye for prowess and ability. He figured out quickly that Serina's rather incapable of lying. if the women are as strong-willed as he claims, he could just be looking to take Almelia's hand in marriage only and otherwise leave her to her devices (and maid).
I guess you could call that the perfect outcome in such a society of nobles.
Estelle is a commoner and seems fine with remaining as a commoner, so refusing a noble's offer isn't that outlandish to her. She just wants to protect her friends and hometown, I don't think anyone can really fault her for that.
Looks a bit too easy for everyone involved, if you ask me. Something's bound to go wrong soon.