I personally think Newark Airport should have all or most NJT trains stop at the station until the PATH extension is completed. It looks like quite a lot of NJT trains skip the station during peak hours, which is bad considering EWR is becoming more of an important transportation hub for travelers. This problem will be worsened when the PATH extension opens up the station to the surrounding area and brings more commuters arriving from the towns west. Why did they even consider building this station in the first place instead of building the AirTrain to Penn if they will have almost every express on the NEC/NJCL skip it? I don't know how the NJCL summer expresses work but they should at least stop at EWR if they don't, since some tourists use the airport to get to the shore.
Train systems ridden (excl. airport trains): Amtrak, CTA Loop, D.C. Metro, JR (Central, East, West), Keisei, M&Erie, NJ Transit (NLR & HBLR), NYC Subway, Osaka City Subway, PATH, Shizutetsu, TDR Monorail, Tokyo Metro, TTC Metro/Streetcar