This article has been put together really well, good job! If I could add one thing it would be to pay attention to the the times that you are bidding.

There are certain times of the day and week that have less bidding traffic on the bots so you might have a better outcome with the unlimited ROI bots.

I would recommend to try to do your most heavy promotions when you think Steem price is at a low, your ROI will greatly increase if the price of Steem goes up during the 7 days.

Thanks for putting this info together, I have resteemed.