Lake Austin was one heck of a Sunfish lake a couple of years ago.
I have caught many of nice fish off of that lake.
"fish 'till I drop" is 100 percent correct. Since the grass carp destroyed all the grass beds there went the Sunfish.
As for the brush piles you can usually pick up some nice Bluegill and Redear off of em.
Overhanging tree limbs will hold the Redbreast. Hopefully the sunnies will adapt and the fishing will improve over time.