"credit card touring" so that means just riding gear. I haven't toured a lot lately but all the camp touring I did younger was with the amount of gear I see people doing nowadays with "credit card touring", a handle bar bag and medium stuff sack strapped on the rear rack with camp pad. I'd be inclined to pare all the gear to one small duffle strapped on the rear rack and as far forward under the seat without interfering with legs and some combination of front bag or frame bag for phone/snacks/camera/windbreaker. That's simply from the standpoint of wanting the lightest and most aerodynamic set up and ease of one package.

Now if you're wanting to carry a larger wardrobe than minimal or don't care about light weight the panniers could come into play but I'd get the smallest ones you could find. These are pretty good.

http://www.jandd.com/detail.asp?PRODUCT_ID=FSBP