Collapse of cosmos over critical density?

Some say that the universe would collapse if the amount of matter and energy in it were just sufficient to halt the outward expansion of everything. But I wonder: Even if all of the matter began collapsing together, wouldn't space itself continue to expand, creating an otherwise empty universe with a hypermassive black hole? Can massless space be pulled by gravity? In the "balloon" model, this would be like all the matter pooling on one side and then into a point. Or does the "balloon" model of the universe allow gravity to pull the balloon into a smaller shape?

P.S. Would it matter if gravity is confined to the skin of the balloon or if it can propagate across the inner volume?