I mean the problem with Bonney to me is that she's a former captain that has the trait to be glutunous, just like Luffy. She's also has an aging fruit which lends her to not fit into any role in the crew in particular on the SHs.
She fits much better a another mini-Law since she has no real role or connection to the SHs. Her story jsut seems like a retelling of Rebeca and Kyros story, an emotional past for a character (Kuma) in which the daughter is the emotional centerpiece to make you go ":(".
She's also extremlly tied to characters related to the revolutionary army, Vegapunk/Kuma, so to me it's likely Kuma dies at the end of this arc and she and Vegapunk go join the Revolutionary army. It's also a good excuse to have one of the worst gen show up at the last war, since they're always involved in these kind of events in movies and such.