Brook's bounty will most likely be comparable with Franky and Robin's but expect Nami and Usopp to share the spoils for Ulti. Doesn't really make sense for Nami's bounty to be above Ulti's she hasn't earned it.
Post Wano Bounties (minus the M3) are looking sumin like this to me:
Brook: 483mil (not sure how but will prolly be sumin like this )
Usopp: 300mil? (not really sure what Oda does with Usopp tbf, maybe 400, since I predict Nami and Chopper will get a 200mil raise)