Looking for ideas... mid-atlantic to maine ... planning on a night or two at seboomook near the golden road

Doing a car camping road trip with my kid this year. Heading to ME from Maryland. Did a similar trip last year but we wanted to go in with a /bit/ more of a plan. Had an absolute blast, but was a bit of a whirlwind. Places we're planning on going (in no particular order) ...

• York Beach (went there last year, visting nubble and freezing our feet off in the water)
• Boothbay (to see the botanical gardens / trolls)
• Acadia
• Spending at least a night at Seboomook campground near the golden road (see below)
  • I /think/ the b52 crash site is near here
• Baxter
• Maybe drive mt washington (did that last year, not sure if we want to do it back to back)

We like seeing neat stuff. Interesting drives (did 2-3 hours on the golden road last year ... we both had a blast just with the drive). Drove camped on the Kangamagus as well on that trip (wasn't planned super well, tons of fun, but LOTS of driving). Historical stuff (tanks, planes, sturbidge village, willamsburg etc), museums, hiking (vigorous walk level, not looking to drop 15 miles in a day), natural "wonders" / oddities.

Going to have ~9-14 days, don't mind driving a few hours. Any places to definitely check out? Doesn't have to be Maine, anywhere adjacent NH/VT/NY/etc.

Kid and I are planning on spending a night or two at Seboomook. We drove a big chunk of the golden road last year and loved the drive. I'm not super familiar with what's around there. Do folks have recommendations? Not expecting anything remotely looking like civilization, just places to go / hike / see stuff.