During winter, rainbow trout can help feed LMB. They are easier for LMB to swallow than TP or BG due to fusiform shape. One issue I ran into last winter was stocking 100 pounds of both larger (10-12 inch) RBT and smaller (4-6 inch) ones. The big ones grow extremely fast on a feeding program and within six weeks are too big for almost all bass. This year I'll stock 2 to 3 times more smaller RBT than bigguns. Bigguns are great fun to catch during cold months (cold being any temp below 55F where I live), but smaller ones do more good for LMB.
I think this a very good idea and one that your LMB will respond to favorably. I also think RBT present a promising species to fill the gap left by TP under the scenario of this thread's topic. If the RBT stocking can occur after water temps have substantially lowered LMB feeding demand, there might be greater potential as there may be less attrition allowing for greater spring standing weights of RBT. Like the tilapia, they represent a disappearing species and seem almost ideal for this purpose.
My goal was to establish nice fishing and wildlife ponds through habitat construction, fish species choice, and removal of fish through angling. My neighbors and friends help with the latter. Its just a hobby so I try not to let setbacks get me too stressed.
I like your approach to this and despite any setbacks I think your goal has been exceeded. The management from a harvest perspective I think has been done very well. Given your pond's age, it is clear that the trophy above was grown from offspring of your original stocking. The partial winterkill may have assisted with that but all the same Well Done!