Stacked diacritical marks and line spacing.

I’m trying to decide between two options for vertical metrics in a typeface that covers Vietnamese and Pinyin. The first is to use line spacing that’s loose for text in other languages, works for Vietnamese and Pinyin, but is tight as all caps with Vietnamese and Pinyin. The second is to make all caps in Vietnamese and Pinyin look good but everything else looks like a collection of poems.

I’m inclined to go with the first option because it’s unlikely anyone will ever set Vietnamese and Pinyin text in all caps. And anyone typesetting all caps in Vietnamese or Pinyin is probably using software that allows leading changes. Does anyone have a reason to go with the second option or a comment on the first?