Why is Les Mis such a phenomenon show? Everyone always feels it has to be huge... I agree with grog, you don't want to overpower the show, you want to enhance it.
One of the best pieces of advice that I was given with regards to designing lights for a musical is that you don't design with your eyes, you design with your ears. It is all about finding how to evoke the emotions that the music has through light.
If you have ideas like you want high side light and a good template wash, what you should do is sit down with a drawing of your
theatre and figure out how many units you need to make the wash even. All you need to know is how high your elecs are off the deck and how to use a protractor (for the beam angle of the fixture).
It sounds like you have the right ideas, so run with them!