This is very interesting, Captain Jack. And rather hard to read
My thoughts on the cost to build and upgrade a bank: I think 2M gold is a very small gold investment to start a bank. I think the initial cost to start a bank should be 5M or 10M gold.
Then each level upgrade cost gets more expensive:
level 1: 10M gold + 100 credits
level 2: 2M gold + 20 credits
level 3: 3M gold + 20 credits
level 4: 4M gold + 20 credits
.
.
level 20: 20M gold + 20 credits
total: level 20 bank: 219M gold + 480 credits
That size bank would take a while to build as opposed to 2M each level which would only take 40M gold for the highest level bank.
I think the 100 credits +20c/level is good but maybe too expensive.
Other thoughts:What happens if a player opens a bank and then becomes a pirate? Does the bank "Close" until they get a new nation and meet the requirements of that nation to start a bank?
What does it mean for a bank to be closed (due to a ban/pirate flag)? Is it put on hold so no deposits/withdraws and no interest is calculated?
Will each bank have a description page that the banker can modify?
Will players be able to rate banks (thumbs up/thumbs down) so other players can get an idea of who is trustworthy and who isn't?
Will I be able to see every nation's policies regarding banks so I can choose which nation to join if I want to change nations?
-Captain D