I'm doing a bit of research and compiling together information on different approaches to constructing a composition in a digital painting, and the tools people use to help them with this. My intention is to find the one best suited to my style, but also be able to give others advice on techniques they can make use of in their work.

So I want to ask you ladies and gents how you go about composing your digital paintings.

Do you use 3D tools as a help? If so, which ones, and why those specific ones?
I've looked at Tonic's work using SketchUp here: http://www.conceptart.org/forums/sho...d.php?t=146591, and this looks like a very practical way of setting up a composition, and one I intend on trying myself.
Are there any disadvantages to this method? Do employers prefer that you don't rely on a tool in this way? I've seen people describe it as a crutch, which sounds negative. It is, of course, a good thing to know perspective drawing, but when a tool can help you get good results in a faster way, are there any reasons not to use it?

Perhaps you prefer using traditional perspective drawing? Why?

To what extent do you use reference images to set up your composition? For everything, or perhaps only the most important parts of the composition? If it varies, why?

How would you go about finding the pose you want a person to have, and then get it onto the canvas? Do you prefer taking pictures and use them as a reference for this, or do you like using one of those small wooden guys to create a pose for your character? How would you say this compares to the use of Poser or similar software, where you can manipulate a model into the pose you're after, and in this way get a reference for your drawing? Which is more convenient?

Are there other methods you would like to share?

I apologize for the question mark carpet-bombing. Essentially, I'm looking for different views on what you perceive to be an effective and/or convenient tool/technique for setting up a composition in a digital painting.