One of the great things about the Etherwave Pro is that its center is shifted substantially to the left of the player, and the pitch antenna is fixed to the end of an extension (appropriately dubbed "the Cuban cigar" by thereminist CRL).
This means that the instrument doesn't get in the way if you want access to pedals and other devices on the floor in front of you. All you have to do is sit slightly to the right. In order to do this, however, you do need reasonably long arms because your left hand must still control the volume antenna.
I have been thinking of making a video showing some of what is possible with an E'Pro setup of this sort, but I'm not sure how many people would find such a thing useful. The equipment involved is more complicated and more expensive than the sorts of devices most thereminists either have access to, or any particular interest in.
Most people just want to plug in and PLAY.
The kind of system I am talking about requires that you plug in, plug in, plug in, plug in, plug in, plug in, plug in, and THEN play. LOL