Resteem services follow you, in the hope that you'll follow them back. By following back, you essentially give them free money (and appear more desperate: if you don't follow them back, they'll still follow you) and also allow them to take control of your feed.
To improve upon the existing model, I've done some maths. There are a few things I've assumed. The first is that every 26000 followers causes the price to increase by 1SBD. Assuming that all profit is paid out to followers at the end of each day payout per follower is calculated as total_profit/followers. If you want to make money for yourself then total profit is (total_profit/followers)*percent_to_followers and percent_to_followers is the amount of money that goes to your followers. If you set it to 75% then every follower gets paid ~0.002SBD per 100 posts resteemed (compared with ~0.003SBD if 100% is paid to followers).
I'll try and develop something along these lines (code will be open source of course). Note that if many people run this code, you can follow all of them.
I'd also like to prevent people from resteeming poor quality content, and will add some code with a blacklist of users – and a plagiarism detector.