Concept art process

After reading the article about a professional going through the long process of concepting an idea to creating a finished, polished illustration. The artist talks about gathering reference in order to paint a truly believable scene. She also talks about composition and flow lines. I'm going to relate what she does with the process I currently take (soon to change).
One thing I do do is collect reference. Not as much as I probably should, but I still gather valuable images of cloth folds and certain character traits. I tend to start straight into an image with a rough idea, and work out the issues as I paint. After reading this, I know that I could improve my artwork ten-fold. Maybe that's what I need. More planning.
The artist spends about 35 hours on the final image. It looks very complete and polished. I have tried and tried again to spend more than 20 hours on a piece but I can honestly say that the longest I've ever spent on a painting is about 15 hours. I'm either lazy (which I don't feel I am) or I just get fidgety and want to move onto another idea I have. I'm actually planning to do a painting where I spend at least 24 hours on it. Complete with planning, reference, thumbnails, the whole shebang. I really think in order for me to improve more I need to complete these valuable steps.
I have a vision of where I want to be in 2, 5, and 10 years. I have a very long way to go in order to achieve my goals, so I'm looking for anyway to improve. I think I've just got settled in my ways, and I need to induce some more fire in the furnace. I think my technical skills are decent and my mind is full of 'cool' ideas, but I think I need to branch out  a bit more and try new techniques and mediums. I used water colours for the first time the other day, and I really enjoyed it. I'll definitely use them more often.
I used to think using reference was a kind of cheating, and believed all my favorite artists just magically came up with all the believable concepts and illustrations. With the exception of Marko Djurdjevic (claims he never uses ref), almost all of them must use reference. I know use reference for almost all of my paintings. Sometimes though, I just like to paint with no reference, more landscapes mainly. I still use all the laws of landscape painting; perspective, colour theory, light... it just feels more freeing sometimes, to just paint straight from my head. It might just be me. The strange thing is that I always use reference and thumbnails for my 2D work at uni, and I think it's some of the best work I've done. So why the hell have I not f*****g noticed! I think I've finally found the next step in order for me to progress to where I want to be.