As you know, the common theme is going to be to keep your shots under 50yds at max...but I have one suggestion that I think might help you knock the birds down that you are worried about. Use #4's.

I hunted with #5's and 6's for many years thinking "the more BB's the better". I had flip flopping birds on occasion and even a couple times had to make follow up shots. One time I shot a full strut tom straight in the face at about 45 yards with regular lead #6's and he did a full roll, got up and started to fly, I luckily shot him out of the air and he had more holes in him than a screen door, but many of the pellets when i plucked him were only skin deep. I decided that since I was using a 3 1/2" shell I had more than enough BB's anyway to just move to the #4's. I can tell you it was a stark difference. The birds just hit the deck now. I've shot some at 10 yards and several at 30-60yds and they just look like they've been hit by a heavyweight fighter instead of slapped by several angry women like they used to. I haven't patterned my shells like you, but I can tell you the results are unmistakable to me. Good luck!