They're not going to go to Nara (been before), but definitely doing Himeji-Kobe in the same day.
But within Kyoto isn't there a day bus pass at 500Y?
I guess it's that possibility of just taking a direct train from Tennoji to Kyoto that's very attractive. Is it that crowded on the Haruka? If can board and get a seat when people get off at Osaka station I don't think they'll mind - pp who travel with kids have different priorities, I think the transfers just take longer for them.
I have very limited experience with Osaka, been there only on a day trip so I don't know if they need to be worried or not.
Will ask him to explore the Kansai Thru pass too!