Is there anyone out there who has added foam to their seat to make them sit higher? I am quite short in the torso and find that my life jacket is always in the way when i try to roll. I put in a 1 inch piece of foam on top of my seat and have been using it this way at pool sessions all winter and really like how it is so much easier to get the front end down as well as not feeling suffocated when setting up to roll. Now... I am concerned on how it will feel on the river, whether the boat will be super tippy.