Keith... I really like your work... colour, energy, motion. Can I suggest a bit more contrast? That is, the texture across your work is "even". If you allowed more areas of "blank" (less active) space, which then contrasted with **BOOM** some energetic, active areas, your work would become even more dynamic.
Just my initial reaction and comes out my graphic design background. Contrast creates excitement... surprise the eye with a break or change in the pattern of motion... that would be my only suggestion.
