I wouldn't mind a system like you describe. There have been times where on FB I used the feature they once had that allowed you to show nothing but sponsored posts/ads in your feed. It was a way of shopping for things I didn't know I was interested in that their algo determined I likely would be. And honestly I sometimes found great stuff like that.

I wouldn't do it often, but if my having the option to do that helps financially bolster the platform, win-win.

I would expect that the location of the ad viewer would have an even bigger effect on advertiser interest in them than STEEM, unless the company accepts crypto as payment.

I like the idea of splitting the money between various stakeholders. So when you watch an ad you get maybe 30% of the ad revenue, the rewards pool gets 20% and 50% gets split between everyone who is providing infrastructure.