One way would be to distribute the sbd earnings from the bot posts (like the daily picks and comments) proportional to the delegation.

Hmm interesting thought. Still, I wouldn't want people to invest in the bot for a ROI, because than bidbots are much better anyway. But if getting a little bit back makes people give more, than why not?

And you are right, distributing daily SBD income according to vested shares seems like a good idea.

Maybe some automated SQL script to gather the data from the delegation and assing the SBD rewards proportion to sponsors.

Why SQL? I don't want to maintain a SQL server. The beauty of the bot is that it is (except from some very basic caching) completely stateless. All statefulness is externalized by the means of the blockchain. I definetly want to keep it this way at all costs. Having to manage state makes stuff from an engineering perspective extremely complicated and annoying.

And you , as creator, take like 5 or 10% cut of the rewards, to keep the bot running.

Maybe in the long run. However, truth is, I wouldn't be so generous in the beginning. Currently the bot does not pay for itself. So maybe I would start with more something like 50/50 to make sure server costs are covered.
Again, I don't want people to invest in the bot to make money, but rather to support content creation and put something automated up against the inflation of bidbots who do not care about content at all.