Hip Hop Slave Sabre

I'm thinking a red strip up the seat tube for a rear light

EL can't generate red (only blue/green/white as far as I know, I don't know the technical limitations or reasons) - but you can obviously run white and gel it red (or any colour you want).

build my own invertor to run off a LiPo rechargeable battery which could drop in the seat tube and weigh considerably less than what you have

If you pull this off let me know as I am a bit crap at all that kind of carry on, I usually find something close and backward engineer it to what I want, I don't think I have enough brainage to work with Li-Po (!!!! do you mean Li-ion??).

. . or a none contact dynamo type system driven off the rear wheel (intensity will vary with speed quite a bit though).

I never like the idea of something compromising the ride, as trivially as it may !