I would hate for you to loose the movability too. Do you know anyone who can make a 2' x 4' platform out of 2 by 6's.
That would give you 6" of height and make it so you can slide it under the table when not using it. Or even make it as long as the table is when it is extended.
My problem is just the opposite. I am 5'9" and end up with a back ache when I use anything to cut my fabric, etc
Good Luck