re: Newport or Cape Cod?

Newport for me, any time of the year for a day trip. I would also put Maine ahead of the Cape. Kennebunkport is about the same distance as Newport.

If you are leaving in a couple of weeks and are going to see the peak foliage, you may be better off going more North than South. I believe southeastern Maine will be in peak foliage season in early to mid October, whereas Boston/Newport is more mid to late October.

If Fall foliage is a significant reason for going, maybe you can make your decision when you get there. If Boston still hasn't peaked, go North into Maine. If Boston is in full color, go to Newport. Just my two cents.

Overall, I love Newport, because once you get there, it's all relatively close. Maine may require some driving around.