Thanks for your comments!

There's a lot to think about here. It would certainly be possible to include votes for self via a bot as a self upvote, just as any other self upvote, that's a good point. Part of the confusion here is that the official terms for Steemit actually say that using bots is prohibited (although this rule obviously isn't enforced) - so adding a metric that considers bots would be a sure sign they need to update the terms too. That said though, I don't see how this can be fully effective, since it is not fair to reduce the rank of a profile just because it receives votes from bot accounts, since bots can be paid by people to vote for others without the account owners knowledge or agreement. This therefore means that account owners will always be able to vote for themselves via bots, using sockpuppet accounts. I don't see a way around this that is fair.. Unless the metric for bot votes is a completely separate one that does not have any effect on the 'generosity' metric.

If I have understood your 2nd point correctly here - the algorithm I have proposed actually already takes your point into consideration, since gaining a high generosity rank will not be possible without upvoting a range of other accounts (relative to the most generous account).