Bon Clay bounty should be higher than Daz Bones's, for the same reason Sanji bounty should stay higher than Zoro's.
Das Bones and Zoro are just "strong guys". For that, Navy have a ton of those as well. You REALLY gotta set yourself apart for being such a threat just by being strong. Maybe at EoS, when Zoro's power will be actual stuff of legends.
Bon Clay and Sanji (with raid suit) have gimmick abilities that can create havoc to entire organizations and countries. This kind of Threat can't be dealt with brute force.
"But Observation Haki...."
Observation Haki is the most inconsistent thing Oda has ever created during all these 20+ years writing One Piece. Sometimes it works, sometimes it doesn't. It can be used to track movement at the speed of light, sometimes it sees "the future", sometimes it's just what the person is gonna do as an attack next (shouldnt it be future sight as well?). Sometimes people sense others automatically like the 3 sensed the swamp guy whose name I dont recall right now, sometimes you have to "concentrate" to sense stuff.
Even with that, how many marines actually have observation haki? Do they have it on all the times? Will they always be on the places Sanji can infiltrate and cause chaos?
By the nature of Bon Clay's skill, he can't have that huge of a bounty, because people won't know it was him that caused problems, so he won't be notorious. But Drake is a marine and if he doesn't report that one of the SH's have invibility power, he is not only a moron, but an incompetent one also.
But then again, it's Oda we are talking about. Sometimes bounties mean nothing, sometimes they do mean something. He likes these ambiguous things.
