Solid article and yes you need more data.. the best way to go about it would be to check the payouts to bots and rewards on some of the shitposters I feature in the shit post diaries of my blog. Some of them have been running it over and over for a prolonged period of time. It would also likely provide you with good data on which bots are the most profitable. The most popular ones I see shit bags using is buildawhale and appreciator, upme is in there as well.. Here is another post that detailed what you are trying to figure out https://steemit.com/steemit/@gmichelbkk/is-it-still-profitable-to-bid-for-steem-upvote-bots

Much of it depends on the price variation between SBD and STEEM>..