Charlie?- Charley? I've seen it spelled both ways, has always been a hero of mine. I think one of the reasons you're finding yourself drawn to something that's barely audible; and 'hard' to listen to, is because you're drawn in by the FEELING. Congratulations. That's what it's all about. (I prefer to deascribe Pattons sound as 'rustic' -heh-heh)
    Pure and simple, Patton gets right to the heart of what it's all about. However, make no mistake, Patton was an highly skilled musician, capable of playing many styles (as you know, from your collection). Charlie didn't seem to care what style he played in, as long as folks were willing to listen, and most importantly, pay. That goes for his lyrics as well. His lyrics went all over the place; even in the same song.
    If you want to find out more about Patton, I highly reccomend a book by Stephen Calt and Gail Wardlow called 'King of the Delta Blues'. Unless anything significant has popped up over the last 10 yrs. this book has all you'll ever need to know about Patton.