That's probably going to be necessary here in America. If anything, the South and West should think about splitting some dioceses, and the Northeast and Midwest should think about combining them. We also need to shuffle the metropolitans to where Catholics actually are now (no reason to have a province in Hartford and Boston, for example).

We have 193 dioceses for 75 million nominal Catholics (400k per diocese) and 15 million active Catholics (80k per diocese). Any diocese with less than half those numbers should be combined. Any diocese with more than double those numbers should be split.

Metropolitans should number about 30, and have about 5 suffragan dioceses each.