I checked flights from MCI to the three airports. Although the fare to PWM is about $70 more per person than BOS and MHT, the rental car would be about $100 less. I think I would much rather make the drive from Portland than Boston, and my wife has never seen Maine. I definitely would prefer the train over a bus, and my wife could keep her AGR account active. Is it worth upgrading to business on this train? The cost is about $8 per ticket.
We will be there in early May, so hopefully the weather will be good. I really appreciate everyone's suggestions.