Thats so cool! i would say from my experience, try and make the sculpture easy to assemble. Make it in large pieces starting from the bottom up (or top to bottom if youre that kind of person ;D). That way its easy to assemble and then strong once you have it assembled in case it is dropped or something like that. PVC is a great material to use when fabricating something like this, ESPECIALLY if you want it to have that futuristic "plastic composite" look.