Whatever we do, I would like to avoid an arranged marriage between them - in canon, she's already in an arranged marriage, and it's essential to her character arc, and also why she joins the phantom thieves. Her father is essentially selling her off to her fiancee for his political career - the fiancee and Haru's marriage is his step into politics - and they have to change her father's heart before that happens. It's not good, but it's what spurs her to no longer be subservient to him and awakens her persona.

However, I could potentially try a Pokémon AU with her! It would be fun to have Haru part of a food conglomerate (we can just assume Big Bang Burger and Okumura Foods exists in the Pokémon universe, and we can probably run similar to canon). I'm not sure where we could go with it, though.