While the layering of colours shows a lot of patience, a little more study of how light actually falls on objects could be useful in determining where to place the highlights. Simply making the middle of the armour plates brighter doesn't represent a natural placement of the light.
The subtle highlights on the end of the lascannon's barrel, however, is great.
Did I ever mention that the reason I wrote vehicles out of my SM list is that I hate painting them? The dreads I keep because I just love them, but I freely admit to not understanding how to paint anything large and mechanical. Your comments about the light are definitely right on though, guess I'm just not sure where to go from here for strategies. Clearly just looking at well painted figs is't clicking for me. Need someone to spell it out I guess.