East Coast US good nature spots (vacation recs?)

Thinking about planning a trip this summer up the east coast, probably do a loopy thing so one way more towards mountains, back along the coastline. All the way up to Maine (starting from Alabama so pretty easy to do a long loop!).

We are nature folk not city folk obviously! And will have my dog along so please suggest places that dogs can be (ex most national parks are not dog friendly, they aren’t allowed on any trails in many of them). We have a converted van that is self-contained / dry camp / no hookup.

Looking for specific suggestions…I can find parks and forests and whatnot, but looking for things like:
Is there an excellent trail you love (6 miles or under, mostly)?
Nice dry van camp spot you know of in some national forest or beach or such?
Lovely little tiny cabin you stayed in or cute motel in middle of nowhere?
Good whale watching spot?
Nice beach that allows dogs (I know a lot of shorelines do not allow them)?
Good picnic lunch pull offs?
Nice restrooms? haha, no seriously, finding flushies in middle of nowhere as i’m sure ya’all know can be hard, and sometimes it’s just nice to have running water lol. Or even a decent vault toilet that is maintained.

Feel free to DM me if you don’t want to put your special spot out here that can easily come up in public search. :)

I can vouch for the Finger Lakes region of Upstate New York, where there are a lot of great dog-friendly state parks with good short hikes (lots of scenic waterfalls!). Watkins Glen is the most popular, but Treman, Buttermilk, Taughannock, and Letchworth are also great. I could give specific trails if this interests you; most involve going up the gorge and down the rim. These do have camping but I’ve never camped there. The state forests also have a lot of great camping and hiking and are much less crowded.

The Adirondacks are also really nice, but I don’t know them as well and have only backpacked longer trails. Also dog-friendly.

Chauncey Creek Lobster Pier is a fun lunch stop in coastal Maine.