What's wrong with "The Harmony Tour"? Sounds good to me.
I don't think he's ever used opening acts but if he did choose one,I'd go with Norah Jones for a "today" choice.
Otherwise,I'd pick an established act but not one that would overshadow him,America maybe? Just guessing. Later!
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"A knight of the road,going back to a place where he might get warm."
- Borderstone