Ah let me introduce you to the lovely Philadelphia International Airport Domestic Terminal, located in the lovely Tinicum Township, Delaware County

(OK, so the place is dive

) From Harrisburg, I'm kind of guessing here, but the whatsit (western?) extension of the PA Turnpike to Valley Forge/KOP, then 76 to 476 to 95 gets you there, and all you've done was circle around the outskirts of the city

a little further up the airport highway and you've reached the international terminal, which OMG is actually located in Philly
Honestly, getting to the airport really is not bad at all. The actual design of the airport is a whole different story, but if I had to choose between Reagan and Philly, I'd take Philly. Starting a drive at 2am, to arrive at 6am for an 8am flight is SOOO not on my list of things to do. I know this adds so close to the cruise, but maybe you want to consider leaving on Friday night right after Nicole's last class and driving to Reagan then. I would not be very confident of my ability drive and stay awake at that point in the night, even though the tradeoff is no traffic. But that's me.
As for the getting lost

Next time call Dan

I've been through most of the city having grown up just outside of it. Even lived in 1 of its cemeteries for a little while, but I was young and don't actually remember that. My dad and his siblings spent their entire childhoods in the same cemetery. We're an unusual family

But I've lived in VA for almost 8 years now, so I'm not up on the traffic.