We're usually talking about individual bounties, which is why I thought about the average bounties of the different seas. We already know, that it's 3 mil in the EB, which is the weakest of all Blues. Considering West is the opposite of East I'd guess the West Blue could have around double the amount on average, so 6 mil, while the South and North Blue could be somewhere in between with 4 and 5 mil.
Then we have the Paradise. We know that Bellamy was called the Big-Time Rookie. He was a special and promising pirate so the average bounty in the Paradise should be lower than his 55 mil from back then. My guess is 30 mil on average. This is 10 times the amount of the EB average bounty and is reflected in Luffys bounty as well, who was the strongest pirate in EB but only of average strength in the Paradise.
I'll apply the same logic to the NW as well. The average bounty there could be 300 mil Beli, which is 10 times the amount of the Paradise and 100 times the amount of the EB. 300 mil Beli is also Luffys bounty, when he reaches Shabondy together with the other Supernovae, who were the most powerful pirates in the Paradise but only mediocre in terms of the NW. 300 mil is also the threshold, where it becomes difficult to raise your bounty even further, according to Jimbei. Only elite pirates get past this bounty.
So what do you think? Is this a realistic scenario about the average bounties of the different seas?