Luffy - 4,500,000,000 (current bounty x3)
*I'm tempted to say 5bil but Blackbeard is typically a step ahead of Luffy so it makes sense for him to achiever the 5bil mark before him
Law - 2,500,000,000 (+2 bil)
Kidd - 2,470,000,000 (+2 bil)
*Law has a higher bounty than Kidd atm, so no reason to think Kidd will have a higher bounty for achieving the same feat.
Zoro - 1,800,000,000 (Luffy's bounty x 0.4)
Sanji - 1,777,000,000 (Back to 7 pattern)
*Zoro has better feats this arc but at this point it's pretty obvious that the Zoro/Sanji bounty dynamic will stay.
Killer - 1,200,000,000 (+1bil)
*Killer will scale to Kidd. Regardless of feats, if Kidd has a high bounty, so will Killer. Killer's bounty is usually btw 0.4 and 0.5 of Kidd's.
God Usopp - 700,000,000 (+500mil for taking out P1 & Ulti).
*Imo Usopp's bounty will remain the 4th highest in the crew till EoS. He doesn't deserve this atm but I think he'll earn it on Elbaf.
Jinbe - 600,000,000
Nico Robin - 530,000,000 (Only Dead)
*It's easy to over-inflate Robin's bounty coz of how important she'd be after Wano but I think an "only dead" poster will be enough to emphasize her threat level
Franky - 494,000,000
Brook - 488,000,000
Nami - 366,000,000
Monster Chopper - 300,000,000
*Chopper will finally have a real bounty