The missing piece for many quilters is critique. It helps immensely to have others who will look at your work in person and evaluate it honestly...what you are doing well, where you can improve, and how to get there.
Those mentors should obviously have the knowledge and experience to back up their comments and be able to explain what they are telling you. For your part, you should listen and learn from what they say...not take it as criticism, but as critique. There's a big difference. Constant praise can be numbing to growth and quilting in isolation can make improvement very difficult.
Think about how artisans and craftsmen have always learned their skills and risen to the top of their art. All along the way they are guided by those with more experience. It's not a thing of the past. Even the masters need feedback from others...face to face, personal feedback.
It doesn't matter if it's show quilts, art quilts, utility quilts, heirloom quilts, or placemats. If you can find someone whose work you admire, don't be afraid to ask them for guidance. Start a relationship with them, build on the shared love of quilting whatever type it is...you'll both gain from it.