When I first jumped on the Bonney bandwagon (and Perona for that matter) I really liked the idea of a snobby personality for the crew, which I do not see Robin as what so ever already filling. That was the first favor to join. Then Bonney seemed to have that tomboyish yet female physique about her that differs her from Nami and Robin. A unique DF and habit, position and a plausible back story signifying a dream or ambition, especially if she happens to be a huge twist of being a daughter of a noble or WG (Great idea by teh way Scarred Luffy). Also a big personality which could become semi bully-ish and a loner like Zoro. However, this harsh persona is not above crying as we saw during the WB War, and I could see her gradually becoming more playful and childish like Robin did, every once in a while cracking a smile or laugh, but then comically punching or yelling at everyone who smiled back or alluded to her having fun. And of course I already have my own list of scenerios while beign around in the crew but aside from all this, Bonney Idt is out of the story yet and could possibly join SH regardless of her prior notions about them.