I ended up sticking with the 5 LED's..but may try high-bright EL wire in the future. I want it to be REALLY bright, but the LED's just don't have the correct brightness, in a well-lit environment, that they could have. Especially when someone takes a picture with the flash on. Maybe adding reflective tape would help?
They do look great with a non-flash picture and in the dark! We took them to AWA this past weekend, and they got a really great response!
I ghetto rigged it since I didn't have too much time. Basically there's 3 purple and 2 red LED's in there. The purple LED's took WAY more volts than the red, and had to have 2 3 volt lithium batteries attached to them, as opposed to the reds, which only took 1 for both. They lights are triggered with the battery/LED package is put into the cards. The wires touch the battery and...let there be kinetic energy!
I basically did a similar thing to the instructables; except for the Plexiglas, I used baseball Toploaders. I super glued two of them together and drew out my own cards, simply because actual cards aren't going to allow the lights to penetrate, and the plastic-see through Bicycle cards don't defuse the light.
I'll definitely be fiddling around with these more, trying to achieve a massively bright light!