Do you assume that the USHL will cease to function as a "tier 1" entity? If the USHL is eventually dismembered by the OHL/WHL then yes, your idea would make sense.
I can see Muskegon and Youngstown joining the O (though I really do wonder about their financial viability in the O, especially Youngstown), I can't see the rest of the U joining the CHL due to geographical limitations.
If I were the USHL, I would be making a full court press on getting USA Hockey on board to petition the NHL for some type of greater sponsorship agreements and then expand into Minnesota, Ohio, N.Y and Pennsylvania in order to head off OHL/WHL expansion.
Problem with my wishful thinking, however, is that at the moment both USA Hockey and the USHL leadership are paralyzed by this latest NCAA development and really do not have a clear plan on how to address it. Meanwhile, CHL leadership is laser focused on making sure they land on top.