Were I building a light tourer I'd put a triple on it, probably a 48/36/24 or thereabouts, and runa 12-28 cassette. So that's what, about 23 gear inches? You can get a similar effect with a compact double and a huge cassette, of course, but personally I like to keep the closer ratios at the back.
You might want to go even lower. There are few disadvantages to having the extra low gear, and on a long climb at the end of an even longer day, even the strongest can find it a relief.