One surprisingly popular Maine wet fly is the Maple Syrup. When you look it up you'll see what I mean.
Apparently it's the color that makes a difference. It certainly can't be it's "complex design"

Brook trout like a bit of color and in Maine you're fishing for brookies.
Orange, red, and pink grab their attention
So the Partridge and Orange is a go-to for me, but it's sister the Partridge and Green also works well in a caddis hatch..

There's literally thousands of brook trout ponds in Maine and the hatch that best draws the big fish out is the Hex.
One popular Maine pattern is the Kennebago Muddler.
Basically it's a Hornberg with a muddler head
And speaking of the Hornberg, put that on your list too.
The hex hatch comes around in early July.

One website you should check out is Don Bastain Wet Flies.
Don lives in PA. but often fishes in Maine and he's given me some excellent advise in the past.
His Grey Ghost Woolybugger is a fine substitute for the Carrie Stevens original.