My first caution is that garments in films may be the result of post-production special effects - so you may not be able to achieve the look you imagine. So test all your ideas on a small scale so you can experience the real world possibilities. You said you are familiar with EL. So you also know about LED lights, and LED light strips. There are also LED panels for larger areas of coverage. I would also suggest you consider your base fabric. For example using a reflective fabric, or fabric with built-in metalic threads can amplify the lighting effect. That does not mean the entire garment needs this type of fabric, but if you are running a line of lights you could add strips or piping of the reflective fabric alongside the lights to brighten the "line" and also provide good contrast. You can also use glow in the dark effects in conjuntion with the lights. Strontium aluminate power can be mixed into glue, dye, or fabric paint to provide surface glows. There is also glow in the dark thread which can be used to create embroidery appliques or seams on and in your garment.
