Aaron is a great resource! Check out my 190g build, link in my sig. You'll see my LED fixture and the driver board he built for me. There are endless ways to setup up LEDs. Canopy, no canopy, big heatsink, aluminum channeling, etc etc
I think you could use a canopy just fine. Will this be the type of canopy that sits directly on the tank, or is hung over the tank? If it sits over the tank, just build it so the back is open (most canopies are built that way anyways for equipment, filters, etc). That would allow enough air to circulate in.