I would even go so far as to expand on #2 - the quantity should be based on the number of users requesting a "useful" bot.

Useful bots should be something that people want to use. They should be something that provides context to the content when asked to do so.

Maybe an improvement for @jeeves and a way to bring it back online right now is only respond to posts that mention it by name? I'd use "Hey @jeeves, share some links" or something worked into my content.

I'd probably even upvote the comment it left, because it's bringing value to my post without me having to work for it.