Darn it -- wrote out a long thoughtful reply, timed out and didn't save it. Here goes some of the recreation:
A lot about fabric choices are simple likes and dislikes. What one person loves, another meets with cold indifference. I think looking at what others do and trying to analyze what specifically you like or dislike about something is really important. And then, once you develop/find your style (and it can take some time) be true. Evaluate your own projects. Even on what I would consider a very successful quilt, there is always something I would do differently.
I think you have a good hand/eye for varying scale and contrast. That can often be hard, less advanced quilters often go too matchy-matchy, which just tends to blur out. But sometimes "low contrast" is the goal -- even though I like a lot more contrast.
One old technique for the distance viewing was to buy one of the doorway eye viewers, I think cameras/cell phones these days can do a similar thing. When a block just isn't working, sometimes taking a picture and looking at it in black and white can point out the problem.