you should have enough lights to cover your space as/is without needing a mover, though under 5 feet of width would be better to concentrate your light. if you were using a mover for efficiency, i'd only use two lights. conventional wisdom holds that the more light the better, but high times did a test grow where they alternated their 1000 watt lights with half of them on at a time to lower room temps and found their yield only dropped something like 10% with half of the lighting. light movers do the same type thing. i've always wanted a light rail, but they seem not to want to work with cooling ducts that much with the possibility of pulling the duct off it the tape fails or even wearing it out so it tears. as mentioned, moving your lights gives you much better coverage which compensates for lower overall lighting, but i seem to remember reading somewhere that plants don't need constant light and, like the HT experiment showed, lose little with temprary dark cycling as that's how they photosynthesize. i think i read that back in the 80s in cervantes' guide, and he suggested that maybe strobe lights might be the most efficient lighting. apparently not if anyone ever tested that theory.
just don't let your room get too hot.