Paradox,
I agree with Sawgrass, you have to work on trees to apply what you are learning to elevate to the next level...especially the art part of it. It will come but may take some time. Practice makes perfect. This is one major reason why I have so many trees--to have lots of practice in a short time. Try it, it works.
Like you, I learn (the technical aspect) just by looking, reading, or observing but the ART part is elusive. Sawgrass is an artist (that is his gift) so some of us will never be as good even if we try really hard. That is fine, know the limits of your capabilities and accept it (and be happy). We can't all be Van Gogh.
Start looking at trees/bonsai you admire...then FOCUS on the DETAILS. A slight curve at the right place may be the only thing that sets it apart from 100s or 1000s of trees out there. Find WHAT makes them special then you will know which to replicate.
Likewise, look at "bad" bonsai and find what makes it bad (again focus on the details)...so you may avoid that mistake. Be a critique, redesign it (even just in your mind), it is not easy but you will learn a lot from it.
There are practice afforded to you only by advanced materials but most can be done on mediocre materials as well. I do not discriminate between plants, I just do as I feel is necessary. Of course there were times I later learned that what I did was wrong. No regrets, lesson still learned.
Bad is bad, wrong is wrong. Correct mistakes ASAP. The sooner you do, the faster you will set your tree to the right path. It may set you back and recovery will very likely take time but that is fine. Otherwise, you will keep regretting your in-action (likely forever).
Learn to let go. For example, a badly located branch, no matter how nicely tapered and ramified, may be a liability. If it is, chop it off! Some mistakes cannot be returned or corrected (or not as easily) so make sure before committing to those type of actions.
Learn everything you can to manipulate the tree. Wiring, bending, grafting, carving, etc. It is nice to have that freedom to create and not be limited by what the tree gives you.
Set a goal, create a good plan and implement. Change it if you must (and you will) but only to improve...not for convenience.
Good luck!