I see from the photo of Sprague Lobster that you visited Wiscasset, the self-proclaimed "prettiest little village in Maine". Also some of the worst traffic backups in summer :-). We had a vaca home about a half an hour from there for 10 years and that part of the Maine coast is my happiest of all happy places. If you have time to fit it in, find your way to Cundy's Harbor in the town of Harpswell. It is s the most postcard-perfect fishing village cove with a lobster place (Holbrooks) and a gift shop and a bunch of fishing boats and nothing else ... not commercialized at all. Of course there are plenty of other gorgeous things to photograph as you've already seen.
The Maine coast is rarely super hot/humid, certainly not like home for you, but every year there are a few uncomfortable days. We're having those days in MA too right now. Definitely go back in fall ... mid to late Sept is FABULOUS weather in Maine, warm days and cooler nights and sunny, and the crowds have thinned although not as quiet as winter. And as you say the mosquitos and the black flies of spring are gone. And in October cooler but the brilliant New England foliage and something about the sky and air is so clean and bright that time of year.
Oh yeah, I should comment on fashion, this is YLF after all Dressed as you are you, are a bit more glam than "general Maine outdoorsy" style. They could use a little glam!