Entirely agreed that it's nothing but more noise, but isn't that exactly how BF is? Why ----- instead of 5-? Well, because BF of course. The point of the exercise (IMO) is having the bare minimum in parsed characters to achieve the turing tarpit.
I quite like the movable register idea but as you say that's no longer a "BF except lambda calculus" it's some other esolang at that point.
I think my objection about the lack of continuations was misplaced given that appears to be a BF take on the lambda calculus rather than a BF take on scheme.