Im thinking I've got two tools here.

In a program I use called zbrush, there is a function called SweepProfile3d. you define the vertical profile, using curves and angles, and then it makes a circular object out of what you used(like if you were following a pattern on the lathe). then rendering it with shadows and stuff like that, you could see quite easily how a certain shape would look, as well as using a wood texture, and then trying different colours, to see if it would look better with a certain colour finish. you can all download it, zbrush.com, free unlimited demo, I think it might be worth checking out.