Ditch the rain pants, just wear the tights when it rains.

Can you share cooking gear and a tent with your touring partner? If your tent is pretty heavy, can you improvise with a tarp instead? What's the smallest number of tent pegs you can bring and still set up your tent?

I have a hard time believing that you can't just stuff clothing into a stuff sack for a pillow.

Forget the shower cap for your helmet, just grab a plastic shoooing bag from a supermarket if it looks like rain.