Below Portland Maine I would suspect you will find the bottom very similar to yours in NY. Above Portland you will find it mixed and some places difficult either because of ledge, rocks or kelp. Many here have exactly what you have and and you can find many anchorages along the coast which are good for your ground tackle. Suggest you use Tafts Cruising Guide to get an idea of the places you wish to visit and their anchorages. For the past 12 years I use approx 60' of chain and a Delta fast set anchor #10 (22#) and last year was the only time I had an issue around Merchants Row across from Stonnington Maine adjacent to the Deere Is. Thoroughfare.(A bit east of Southern, Maine.)

Be sure to visit Gosport Harbor at the Isles of Shoals (NH/Maine line). During the week, moorings are generally widely available and are free

Make sure you stop off at Snow Island in Quahog Bay (muddy bottom) nice overnight stop over where the water warms up in the summer (N43 49',  W69 54').   Look for me when you sail by Bethel Point.

Timely thread. Might be heading "downeast" during the week of July from Cape Cod.  See where the wind blows. Recommendations on "must see" spots in NH/Southern Maine from the locals?

Nick,
If you make it to Maine, the quickest place you might get to would be Casco Bay. Many Islands and anchorages to go to. Portland if you want city atmosphere but you might enjoy Jewell Is. with trails, old bunkers, and nice beach. Next door to Jewel are Eagle Is. Admiral Perry's summer home open to public, Further east Potts Harbor Dolphin Marina great chowdah!