i see that fiskars is making the same ruler (I think!) in a 12" size, and it is under the name of donna dewberry. It should accomplish the same thing, but you will have to fold your fabric one time to get it into the 12" space. The advantage of this size would be portability and easy storage.
I also love my June Taylor shape cut ruler and think it is amazing, and fast, and accurate. however, I think you do need some basic rotary cutting skills before using it, as it has a very slight learning curve. I start quilters out using it, rather than a 6" x 24", but I am right there guiding them as they learn.
There are so many wonderful suggestions here. Please let us know if you use any of them and how they help you.