Would this be interesting?

I think it wouldn't be too hard to make a shape that means that all shapes connected under itself should be tested in breadh-first order - never used that kind of search, that I can recall, but it might be a fun thing to experiment with :)

Hmm.. i don't think it would need a special shape, when I think about it -it could be used via a special option in a connection-shape, or a Group