What brand/model for touring bike are you thinking of getting?

A double crankset will give you a little smoother shifting than a triple, but there's no reason for a triple not to work well if properly adjusted. If you're pairing a double crankset with a 10 speed cassette (11-36t), it should work well for your current light touring needs. Should you go with a double (compact) crankset, get one with the least number of chainrings in the small chainring... 34 t seems to be the standard for compacts, although you can get some as low as 30t like the Velo Orange Polyvalent crankset.

A triple crankset w/ a 22t small chainring, on the other hand, will give you the advantage that if you ever want to tour with heavier loads, you'll be able to obtain much lower gear ratios. They are paired best with an 11-34 cassette. This set-up will do better without so much huffing and puffing on mountain roads with steep grades.

Most well-designed tourers will not short-change the user. They will automatically come with a triple. Personally, a triple chainring is the way to go on a touring bike.

As far as shifters, it's a toss up. Try both and go with what you like most. If you ever decide to use a handlebar bag, remember that they can get in the way of your STI shifters.