It’s an interesting project and well executed so far, but ultimately I’d like to see advertising more divorced from the voting process. The worry is that should SteemRush be solidly successful... as little as a couple dozen serious clients leads to the entire trending page being filled with paid advertisements. And how does the business model hold up if Steemit and other front ends begin manipulating their trending algorithm? Or do away with a central trending page altogether?
Vote buying for placement has only grown due to the lackluster implementation of the promoted post feature. Interspersing promoted posts with regular feeds is the #1 priority in my opinion. Then people can pay for visibility without buying votes, and the burn of spent funds benefits everyone’s Steem value.
Beyond that, I think a better advertising direction to invest effort into would be to get Steemit and other front ends partnered with an existing ad brokering structure. Anonymous Ads comes to mind as a great potential. Get their code whitelisted so it works on the site, get them to accept and payout in Steem (much better than the bitcoin they use now!). Done.
Then every user can set up their own ad inventory if they choose to. Monetize their content beyond 7 days by placing a banner in the footer of their posts. Advertise their content by purchasing adspace directly in the blogs of top authors in their targeted category. If people go overboard with ads they’ll risk alienating readers, so it’s entirely up to individual decisions & free market on a blog by blog basis.
So in my other replies, I also concluded as you have, that Steemit, in its current form can only support a handful of clients (that's why I'm not even bothering with smaller clients right now). However, I don't want to see straight up banner ads from Samsung etc. I want companies to promote real engaging posts that they already are creating through their existing campaigns.
For example, Google Cloud might promote a video series on d.tube to team serverless development with Firebase's new hosting feature etc. Microsoft doing a tour of their office and promoting some recruitment content etc. I think ultimately ads should as close to real content as possible. We are just so used to shitty ads that we instantly have negative thoughts about anything related to ads / marketing.