I would say that 24 inches is pretty high for a low gear on a touring bike if you expect to tour in the mountains or where it is hilly. So unless you want to tour in the flat lands or like to push really big gears and/or will be carrying a very light load I would get a 24 for the front and/or a cluster with at least a 32 on the back.

Pushing too big of a gear is not conducive to good knee health. I know this is just anecdotal, but take it as food for thought. We met a young man on the TA who had road bike like gearing and he seemed to be doing fine. He was usually first to the top of the climbs. The thing is he didn't make it 1/4 of the way across the country before he blew out his knee. He had knee surgery and I hear he was laid up for a year.