I believe that bluegill are not particularly territorial at this time of year. I believe that they move to wherever the forage is, in particular if the forage is pellets.
The big'uns probably aren't running off the smaller fish, but more likely their presence is intimidating to smaller fish that will probably lurk nearby to see if there are any leftover scraps.
As long as you have representatives of the helmet-head club and half-dollar club available, it sounds like what you're doing is paying off. No need to change what's working, eh?
I've found that I can get the smaller fish to get more food if I buy a bag of slow sinking feed at the beginning of the year. If you're hand feeding, the big fish will dominate the bigger floating pellets and you can distribute some slow sink near the edges. If the little guys catch on you can get them some of the feed as well.
It's probably easier to control the size distribution of your bluegill by manipulating bass populations than it is by specialized feeding techniques.
