You can stay 15 forever while the rest of us grow up and our musical tastes evolve. Out of any band that came up during that neon pop rock movement The Maine has the most of my respect in how they've evolved musically and as people in general.
I understand they want to evolve and be "mature" but The Maine has isolated a core fanbase that started during CSWS. That's why they sell less and less records with each release. I respect Pioneer and thought it was a great record but Forever Halloween are literal b-sides from Pioneer. I don't see The Maine getting any bigger than where they already are.