I love the colors and design of this flag despite being a shield-on-a-bedsheet. Massachusetts' official colors are blue, green, and cranberry.
This is not my design, this was created by /u/interrobang26 from this post: https://old.reddit.com/r/vexillology/comments/jvwq1y/massachusetts_cranberry_and_pine/
I get what you mean with the tree, but despite that I like it. The better symbol would likely be a cod, but that isn't green (one of the three official colors).
As for the cranberry, I think that's what makes the flag special.