I'm exploring my ability to express ideas more rather than the infinite journey for anatomic perfection. They're not mutually exclusive
That's great! the advantage of thumbnailing ideas is that you dont have to worry about the proportions and you can really go to town on the idea itself, and then worry about getting it right later on.
In my opinion, or at least in my own art-theory/methodology, concepts are exactly mutually exclusive with correct/finished drawings. Keeping the distinction and the separation is what keeps your concepts fluid and your finished works polished. That's my take on it.
It might help me win over my fear of backgrounds
I can say from experience that it totally helps to get into backgrounds.
You have mentioned a few times that you dont have a sketch style, what in your mind is a sketch? because I personally would say that almost everything you do would count as one typically, such as the ones you just posted.
Do you mean like a draft for a final piece?