One way to think of it, is like a boxing event. Which fighters go first, and why?
Usually, they try to arrange it so that better fighters come last.
Everything else being equal it goes from lighter to heavier weight class at the end of the evening.
Opinions will difer on wether the Balvenie surpasses the Glenmorangie in terms of quality (though I believe it clearly does). However, I think it pretty clear that the Glenmorangie is a much lighter spirit than the Balvenie.
I'd say the Glenmorangie would be a lightweight, while the Balvenie is at least a welterweight (a sort of super middleweight). The lightweight has less of a punch of course. Its possible subtelty will be lost to the tasters as the evening goes on and the tastbuds tire.
So I say pour the Glenmorangie first.
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