I would also give you this advice - the paper you use does make a difference. Some cardstocks hold up better than others to being repeatedly wetted and dried. SU Whisper White is all right. Tim Holtz uses those manila tags for all his demos.
But really, if you find yourself getting frustrated because of the paper getting too distorted or wavy or degraded, just work with watercolor paper. It doesn't have to be expensive or heavy - a 90 lb. cold press works really well.
And give your work time to totally dry. I find that Distress Inks change for the better as they settle in and dry. The colors lighten and sharpen and even out. I like to do a bunch of wrinkle free backgrounds and let them dry overnight and then they look even better in the morning!