Open (ditch the perimeter rule) or close LaGuardia. The increased demand for regional flights (as the slots at LGA shift toward longhaul or nothing) at EWR/JFK would make larger planes feasible on regional routes. Larger planes = more people = more PFCs = more money for runways.

Also the merger should help on regional routes at EWR since the same pax can be sent through ORD/IAD instead.