My Mother had Essential Tremor, and so do I. For me, I find when it's bad the more support my arm can get the better. Are you in a Guild? You may find some friends there that can help you out. My Bee meets in our local quilt shop, and they have cutting tables set up with mats, we just bring our rotary cutters and specialty rulers. I have found the ruler that has all the slits every 1/2 inch for 12 inches is a favorite. The channel really helps you keep the rotary cutter in position. There isn't much walking of your hand, I fold my fabric in half again line it up and go from there. I've had pretty good success with that. On another topic on the board today they have someone that got a letter from Fiskars stating that they would be manufacturing a ruler that had a rotary cutter attached. The woman wanted to get if for her Grand daughter, she still had hers and loved it.
At one time I had a great deal of neurological pain and had trouble lifting and keeping my arms raised, I was really upset because this pretty much cancelled quilting for me. But I decided I just wasn't going to go down with out a fight, and tried hand piecing. I felt so victorious when I finally finished that quilt. I am so much better now, and this isn't an issue. I guess what I am trying to say, is what you are doing, trying to find a solution to this problem, is great. I thought the comment about the weights was quite interesting.