There are many paths one might take to getting a comp license. Each has it's advantages and disadvantages. Sure track events get you lots of seat time at controling your car at high speeds, but it's hard to beat auto crossing for car control as you'll drive closer to the limit a larger percentage of the time. As for the comp license all it takes is one super-school and a double regional with the scca and you'll have a license that any organization will recognize. Also you have to remember that wheel to wheel doesn't have much in common with track days. I've seen some guys that come to w2w from track days and get freaked out about having someone driving next to them or at the start.
Usually, the cool suit uses regular ice, but I suspose you could sustitue dry ice, but make sure your cooling fluid doesn't freeze up. Then you wouldn't get any more cool.
James