I agree with a lot you say but it is kind of what it is. Bounties are literally a race to a price that you don't know if you will get it.

One thing I don't think is accurate is the licensing of your work. You can perfectly not put your work under an open license if the bounty doesn't get paid.

From my own experience, offering bounties does not work. As much as I wish it would, Fiatjaf is right about all the issues with it getting gamed.