I like Oda's wacky character design! If he didn't have wacky characters, well . . . . then it wouldn't really be One Piece. OP sets itself apart because it takes risks with silly designs like this.
And yeah, after that speech it's easy to believe Franky is in the bag as the new crewmember, but I'm still leaving things up in the air. NEVER try to predict Oda.