AA or DL out of JFK is a crapshoot. JFK's terminals, layout and OPS just annoys me. I avoid AA because of their planes and DL for their service. I live in Prospect Heights BK, the Northern part of Prospect Park and Fly mostly out of EWR even though it's not as convenient. Depending on where you're flying you might be able to use B6 which has great planes, service and an awesome new terminal at JFK.

Alternative to using the subway to JFK from our neighborhood is going to Atlantic Terminal (above Altantic-Pacific subway station) and getting on the LIRR to JFK. It's faster and way more reliable while only slightly more money. Status match to DL and give them a try. If you don't like them go back to AA since you obviously enjoyed them since you are Platinum now. Via a Platinum challenge or maybe a call saying you'd be willing to come back if they gave you Gold status might get you back to high status quickly.

P.S. Welcome to the neighborhood.