Hey Lighttechie, as a former high school teacher I know where you are coming from. I've had students with similar ideas. You've developed some skills and knowledge and you want to use them to do something big that goes along with the big show. But unfortunately, as you just heard from several pros, the truth is "big lighting" can be distracting if not ruin a show. Remember if the audience leaves saying wow those lights were cool they weren't concentrating on the action. Have you seen the Broadway version? The vast majority of the lighting is very subtle. They do a few cool things in the sewers, with the occasional
gobo, and some nice night lighting, but other than that it's all very straight forward.
As has been suggested remember the power of the show comes from the music. Let the music guide you. A few musical lighting conventions to help you. Often there is a subtle light change as a song begins, either in intensity or color. You don't have a lot of instruments to work with so that may be tricky. But if you can find a way to give your stage a good basic wash then have some alternate color washes from above and behind, you'll give yourself something tow paint the canvas with. Songs that should feel small and intimate, like "on my own" you want to bring the lights down and add color around the singer while keeping the intensity the same on the singer. I like to keep my overall intensity for the show down around 85%-90% for most scenes of for a big songs like "one day more" I can punch the whole stage up just a bit. Keep it slow and subtle so it doesn't distract, I really like that idea of designing with your ears.
Finally, special effects lighting is one way you can do something that really does pop. The idea of LED's in the barricade is an interesting one. You don't want to over do it, but it has some definite potential. Check out
www.goldengadgets.com for cheap bulk LED's for wiring up things yourself. Also consider just having some lights hidden in the back side of the barricade that flash in some smoke... I think that's what they do in the Broadway show.
So keep it simple. Don't distract, look for ways to use color to accent.
If I remember right "Icewolf" recently did a production of Les Mis at his theater... and he's got a little bigger budget with more toys in stock than you have. Alex, or anyone else who may have done a pro/semi-pro production of Les Mis, it might be helpful for this discussion if you shared a little bit about where you did do use "cool tricks" and where you didn't in your production. Restraint and simplicity in design are difficult things to teach so thoughts from personal experience could be helpful.