BOOST THAT SEAT!
You have sorted some of the issue in flexibility, and that undoubtedly will have an effect. Yoga and repeated range of motion exercises will continue to improve your physical ability. BUT, and this is a big BUT... the type of roll and whether it is a blend of different kinds of rolls will depend on your body (size, strength, flexibility, etc). Our big emphasis when we teach rolling is SAFE (for your body) and EFFECTIVE (meaning it works and is reliable).
We have some videos out there to discuss some of the differences, but we have progressed with our ethos even since these videos. We teach hundreds of folks every year and we recognize patterns, and even then, we get surprised from time to time.
Some things to be conscious of and stand true for any type of (hips snap) roll:
-You have two levers in the roll, your body and the paddle... when you use one more, you use less of the other in an inverse relationship. The body however doesn't have a diminishing return like the paddle does.
-Every skill relies on the foundation of COMFORT, ORIENTATION, THEN the execution of the skill. If you are having problems with comfort or orientation don't expect higher order function to work for the skills.
-Your strength in your roll comes down to flexibility undoubtedly, but not just the spine. I think that's a misnomer. Hamstrings, quads, hip flexors, gluts, are huge culprits in roll inflexibility and should be a starting point.
Hope this helps, and if you need a class or want to check out our videos, we love to teach and can get you on a program! www.h2odreams.com