I think that these are very feasible ideas. Haters of advertising might paud and consider the traffic that advertising would bring to the site. Google crawler bots rare sites and pages based on inbound and outbound traffic and rank accordingly. The increased traffic to and from would definitely boost the platform in general. You have stated several ways in which they would not be intrusive and frankly the dividends to users based on mvests would be a surefire winner in my book.
I always thought that when the posts were rejigged to include more white space on the margins that it was in preparation for this.