The 1500 rule will be good in many ways, but I think it coincides with the backside of the ballistic trajectory of the regional business model...regionals will be shrinking for the forseeable future (maybe growth at a few, but that will come at the expense of the others). 50-seaters are going away and will be replaced 2-for-1 with larger RJ's, or not at all.

In the event of a true pilot shortage, I suspect great lakes and the like would probably fold in a matter of months...they can't afford to pay livable or competitive wages, much less subsidize flight training or time building for entry-level pilots. EAS service would be lost to a lot of podunk towns, with negligible financial impact to the nation as a whole (slight economic boon to rental car companies).