I too don't like the 1/4 border with the larger sized Speed-EZL.
What I have done is make a frame that fits inside the easel.
Not only does this allow me to make a bigger border but also helps hold the paper flat.

I used 1/2 x 3/4 inch strips of wood I found at a local craft store and some metal corner braces to hold it together. I drop the frame in the easel once the paper is in the easel.