There would be more interest in commuting from Newark to Philly if the last afternoon peak train to Newark left after 5:33 from Market East. If you have to stay late, or have a dinner meeting, Septa becomes completely worthless. You can make a DART bus connection from Wilmington to Newark, but not Churchmans (connections are not available late at night). You can take the 7:32 or 9:28 from Market East, and after sitting on the R2 local, you can sit on a bus (Route 33) for another 40 minutes, and limp into Newark two hours after you left Philly. So unless you're a raging alcoholic and shouldn't be driving, a normal and sane person will bang out that post-PM-peak ride in about an hour. Not too convenient if you ask me.
A.E.'s idea of overlapping service provides the most potential for increased service between Newark and Wilmington. I'd assume DelDOT would have to contract to MARC to provide any service into Delaware? But this would still require DelDOT to step up to the plate and pony up for the increased service. If MARC were only to go to Newark, it shouldn't cost DelDOT much, if anything, right?
I don't think there will be concern for more trains running along the NEC in that stretch, as they should be able to handle the every 10 or 15 minutes or so. However, the layovers would be cause for concern. Either you have to turn the trains around in a couple of minutes, but then what happens to the schedule if you're a few minutes late? And there's no room for connecting service in Newark today. But overlapping service to Wilmington might be one way to get the Marc trains out of everybody's way.
How much increased/connecting/overlapping service could we see? DelDOT in my opinion isn't exploiting the intra-Delaware potential rail customers, and have bus-tituted the sole midday train. Just because Marc and Septa will both stop at a station, will there be actually connecting service? Or will we see fewer and fewer trains going all the way to the end of their lines? So if 8 Septa trains make it to Newark today, will there only be two that make it to Elkton? Same for Marc?
Here's another idea. Since the rationale is that people are going to be driving south on 95 from Delaware to Aberdeen, why not have Aberdeen the connection point? Granted, that's a haul for Septa. Or do you create a new DelDOT service a la Shore Line East. I vision them running from Marcus Hook, Claymont, Fox Point/Edgemoor, Wilmington, Churchmans, Newark, Elkton, Charlestown, and Aberdeen. There's room to put a layover yard south of the existing station, or run it as the connecting service all the way into the base instead of building a connecting light rail. Then the new DelDOT service can take over the R2 express trains, last/first local stop being Claymont, so they wouldn't be responsible for for PA riders. That would be the only through train to Philly, using 30th lower level. They can even take Septa's bomber cars off their hands. If DelDOT runs into MD, then wouldn't they be compensated? Can this be a profit-maker?
Is it time for me to come down from my cloud?