To be honest, I find that Oda failed big time with the Gifters and even more so the Headliners. All those guys are jokes, there is litteraly not one of them worth shit, they are glorified fodder, yet it seems that most SH are at best able to handle those. Basically, only Luffy, Zoro, Jinbe and Sanji seems able to deal with them easily, even Franky, Robin and Brook don't have great feats against them, which sucks.