The Movietube is great, but it does offers some limitations, firts it loses a lot of light! like 2 stop plus what the lens is losing. So the HVX I understand is like a 640 ISO, so you'll be shooting wiht the adpater at 125 ISO or less! if your script involves night exteriors, you'll need a lot of light! It weights a lot and add the Camera a PL lens rods and a Mattebox and you have a very heavy setup, so you'll need a big tripoid along with it's head, I've used the Cartoni C40.
Where I live (Mexico city) you can only rent the Movietube Lt and that takes handheld shots away from the project, even if you manage to hand held that heavy setup, the operator can't frame because you need an external HD LCD. That Problem is solved with the Movietube ST, that has shoulder pads and you can fit it with a HD viewfinder for the operator.
About a single operator, well it depends, if you have rather estatic(not moving) shots, yes, one operator can frame it and pull the focus, but if you have hand held or any other moving shots, someone needs to pull the focus for those.