You can always add a little DE if you want--just enough to make the pressure rise by 1 ppm--and it may help filter out smaller stuff. Don't forget that the pressure rise takes a few minutes though, so add it slowly.

I don't think adding floc is going to help--it is designed to make smaller particles that won't settle to the bottom stick together so it will settle. Sounds like yours is settling fine, so there's no need for the floc.

Good job getting the CYA down to 50--now just maintain your chlorine in the 3-6 ppm range. Actually, I would keep it on the upper end of that, but it should be easier to maintain your pool now.

Janet