Most everyone is posting their ills and I have quite a few myself. Just turned 70, shaky hands, etc. The biggest obstacle I've overcome is holding onto parts while gluing, detail painting, etc. I solved it with one of these:
http://www.harborfreight.com/2-3-4-quarter-inch-articulated-vacuum-vise-3311.html
I took the suction apparatus off the bottom of mine (I have 2) and mounted each of them on a short 2 x 6. The swivel head allows a part to be turned and held at pretty much any angle/orientation. My detail painting is still pathetic compared to some but it's much better than it used to be. Gluing parts is much easier.