Bill,
That 23 inch bass was 123% RW. A real fatty. That is pretty common for the few large bass you have to be really fat since they can eat the stunted bass and large bluegill. How did you stock the threadfin? Big ones(1.5-2") in the spring just prior to spawning is my recom. Did they establish only to die because of cold winter? If this is why then gizzard would be an option. Gizzard come with a more difficult management plan since they can reach large sizes. However they my be the best choice if you really want big bass.
Also have you harvested enough bass? Most people do not. These bass crowded ponds can be tough on shad with so much pressure on the forage. One more for you, what is the size class distribution of your bluegill? If you have a lack of 3-5 inchers you may want to pull out more bass and then stock intermediate bluegill.
The hybrid striped bass would be good with supplemental feeding and/or shad population. Of course this may lower the bass forage, and if trophy bass is your goal I wold not do it. If you want quality bass with a more diverse fisheries they are a cool addition.
Good luck, any ducks showing up in your area yet?
