If it is electric technology it would, in my opinion, take related forms of what we see now.
You should really have a look at the concerts from The Glitch Mob, their performances could be a hint of what you are looking for.
For creating electric music live you need to use a synthesizer or are pre programmed launchpad. It makes MUCH more sense to create a controller to distort a guitar to sound like dubstep then to create a dubstep guitar.
But if there was not any instruments until technology came, you can do whatever you want. Otherwise I think you have to include drum and string instruments, because those are just the most natural to create. (Every from of culture created their own kind of drum and string instruments.)
But in their vidoes you should see that anyone in the band is standing in front of a deck of controller and pads. Without this the only way to make the music live would be a mp3 file... (early Skrillex, running his song on windows media player and jumping around like a madman).
You could make it a lot cooler though: let their decks float around with magnets so the artist can move with it, hell, why don't even put the artist on a magnetic disc and let him and the deck fly around?
And live drums are always better than recorded ones.
Play around with distorted singing voices in the track. Artists all over the world are starting to create their dream language and sing with it.
But light shows and the general feel of the performance is way more important (in electronic music) than the artist looking cool, in my opinion.
Another thing might interest you: take a look at the song Unsustainable from Muse. Dubstep made with a normal band setup, but with very hard computer distortion. You could simply make rock'n'roll stars to dubstep stars, just by using different effectors. Then Bellamy from Muse got a weird guitar like in this video. He can program the touchpad to do whatever a computer can do with sound.
Lastly, probably the most interesting for you is this video.
You could equip artists with these everywhere, let them dance and create music with their dance.
//E Totally forgot about loop artists. Check out Tash Sultana and Dub FX