I want Curator to delete all indicies after 60 days, but should I exclude some of the system indicies?
Absolutely, yes! If you don't, even your .kibana index will be deleted (or at least a delete attempted).
So I only need to worry about .kibana? What about .watches,.watcher-history, .triggered_watches, and anything starting with.monitoring?
All of those. I said,
even your .kibana index will be deleted
It was meant to be inclusive. It was not clear, and I'm sorry for the confusion.