I think most of that would be far more than you'd need though.  You could cut down on the pumping by quite a bit, especially if you cut down on the fish some and you wouldn't need nearly that much light, even over a tank that big that's a LOT of light.  Cut down to 2 kw and you'd still have enough light for low light plants if you want the tank planted.  A lot less if you don't have it planted much.  You could have a heap of lights just sitting turned off for if you want it nice and bright to show it off, but settle for dimmer most of the time.  But you'd get a lot of free light if you've got it set up kinda like a greenhouse like I suggested.  Running the tank a little cooler would help too. 
 
I suppose the only way to say for sure is to build it.  But since it's a dream, might as well aim for best of everything.  No snorkel when you could use scuba gear.