Ye would be awesome if it'd happen like you explained, then she could finally come to terms with her past.. I don't think it'll be Ai x Mitsuhiko, because like Conan told him she's not suitable for him just too much for him to handle. I think she just likes him as one of her true friends. In my mind Ai needs someone who's 'in her league' and Okiya/Akai is/are one of those (as I think even Conan has problems to reach this. What I mean is that hes more like a child) and Mitsuhiko x Ayumi would be a better couple..