That is good advice, and i am trying to do less complex subjects so I can finish them in a reasonable time. Although I don't consider A4 size to be very large. The reason I didn't want to get too small was that I have a tendency to get too picky and overwork. Smaller paintings usually use smaller brushes. In a workshop I took years ago, the teacher suggested that one had more freedom to do washes and shapes would be more recognizable if they were somewhat larger. I am trying to loosen up more. Many artists work on half or quarter sheets regularly. Although for a small object, like a solitary leaf or piece of fruit, I do smaller paintings. The sketchbook I use to paint on my patio in the warm weather is about A6 size.