I don't know if any of this refutes any of your statements. It's just how I see these two characters, and interpretations can differ even when two people discuss a mutual acquaintance in real life. I agree that Tezuka sees something in Ryoma that he doesn't see in himself, but that doesn't mean it isn't there to be seen. Neither of them strike me as being all that introspective; they don't think about their feelings, their motivations, their drive. They just know it's there. Tezuka has learned to understand other people, as Ryoma's beginning to. Understanding themselves is not something either has ever thought to do, I think. They know themselves, they know what they want, and that's enough. The whys are irrelevant. And that's probably why they're so difficult for us to understand as well.