We should be able to pick who we want.
BUT their would be restrictions on who we can pick. So obviously anyone on Silver should can pick any silver.
Gold you can pick any gold between the rating of 75-87, but there's a limit on that too. So you can either pick 1 85+ rated and two under 78 rated players, or 2 82-85 rated and one under 78, or 1 82-85 and two 82 and under...something like that
And then Elite gets access to any IF but the restrictions would be just like Gold but just multiplying it by 3, so 3 87+ rated, maybe 5 82-87, rest 78 and under. Something like that.
Top 100 has no restrictions.