couple suggestions, first one being: try smaller suckers, in regular spots, humps, dropoffs, etc etc. If the suckers dont work, jig up some of those sunfish that are in there. I got my first mountable walleye last year (first fish kept in 10 years) and it had 6 yellow perch in its stomach, granted they were all on the smaller side.......... This summer was a phenomenal year for me for walleye, we boated 175+ keepers and even more shorts, some of which came on BLUEGILL. They will eat them! try to catch the smallest ones possible and give them a haircut, usually i cut half the tail off and either the whole top fin or one of the bottom fins. Usually I'll dropshot them but it can be done with a regular tip up rig and heavier splitshots.
hope this helps, good luck.
E