Nice pics.
Well, lighting depends on what you really want to keep for corals; but then I see what your saying about heat. If your not going to keep any acro's or other high-lighters, then PC is a good route.
I have a 175 over a 25 gallon system and have no heat problems; it just takes having enough airflow to dissapate most of the heat before it is transfered to the water.
Here is a link to Roger's (yardboy's) nano, a 10 gallon with a 175, the last I heard that there weren't any major heat problems; he hasn't been around for a while tho.