Yes, it needs more quilting. Having more quilting will take it from having a fabric panel on the wall to an art piece. If you are having problems with invisible thread, use a colored thread. I use to use invisible all the time, and when I look at those projects these days, they remind me of my awful clothes from the 70's! All the wood and others textures in this piece are a great place to practice free motion. And though it is more time consuming, I also match the bobbin to the top thread - especially in a wall hanging where the back doesn't show. If your tension is even a bit off, the bobbin thread will not stick out. Good luck!