IMO, this Garamond is too light, and it doesn't go well with Operina. I'd try something a bit darker (maybe Georgia if you have no budget).
Another thing is to avoid fake small-caps (also avoid italic small-caps).

The garamond is definately too light. Possibly Pentegraf from Storm Type? Although that may be too mannered. I would have to see.

Eduardo, thanks for the pointer on SC italics. I'll deal with that.

As for a darker text face, I'm looking around for something Venetian-y or Garalde that's a shade darker than that garamond; no such luck yet. Kyle, I'm tempted to think that Pentegraf is too mannered; it's pretty, though. I'd like to avoid sinking large quantities of cash into this, since it's a personal project that I don't expect to produce much in the way of returns. (I'd appreciate recommendations, though; it's always good to expand one's type library.)

If it helps to clarify my intention, the Operina is supposed to be a little jarring; it's only used for some very infrequent technical items. Italics are used for ordinary emphasis. Perhaps it'll improve the layout to tone down the contrast with the text a little, but I don't want to lose the effect entirely.

Thanks for the pointers, all.

When I've worked with Operina, I found the word spacing to be too wide in relation to the letterspacing. How do you find it?

Watch word pairs that need tightening and loosening in relation to the swashy character too. And don't be afraid of the alternate characters, they did a beautiful job of giving plenty to play with. For instance, on the second page you could use an alternate R in "Resolution" to get the spacing in between R and e to look good.

Fun use of a beautiful face.

Ditto Eduardo.