Writing for the deaf and the hearing

A friend of mine and I are taking on a new challenge: We've decided to write a play suitable for both deaf and hearing audiences, but without any interpreting, captioning or voice over of any kind! On stage today there is a variety of plays that are presented to a mixed deaf/hearing audience. Visual theatre, without any words spoken; "normal" plays, with sign language interpreters on each side of the stage (or sometimes what is called "shadow interpreters") or captioning; or mixed plays...