Unless you have a strong emotional need to pay off debt, I would pay as you go, especially since these are relatively low rates. You're doing great with your savings vs. debt.

Having flexibility now as you start your lives will help you make better longer-term-focussed decisions. I say this having been in the opposite position when starting out. If you do feel the itch to pay off, pay highest interest first - but wait at least until the 0% period expires.

You might enjoy the book “722 Miles” about the history of the subway systems. It helps explain why much of it is the way it is, for better or worse - many cities’ transportation systems bear the marks of their development, when they were built and how they consolidated (or sprang up as a single consolidated system). The older and more disjointed the history, like new York’s, the more unique the challenges.