Tracy, good for you. You have posted before about a brood pond, and B Cody referenced that as well on this thread. IMO, that's the best option, and remember, you can growout anything that fits your particular scenario at any given time. If you need more CNBG, grow them out to the size you're targeting. If you want TSF or anything else, grow them out the same way.
B Cody also referred Bruce Condello's LMB in his post. I've been lucky enough to witness his results IRL, and his ability to make XL LMB "location friendly" for lack of a better term. I won't go into his particular methods, because that's his option, but I tried what I learned in NE, and it sure helps keep XL LMB resident to a particular area. Trout could benefit those larger resident LMB, and that's the size class you're targeting for extra calories anyway.
On a pond your size, I think trout would really benefit you in a year or two. At a 10 to 1 conversion rate, RBT would cost $100 to add one pound to a LMB. If your LMB are close to your target weight, then that dollar amount is really cheap IMO. If you're feeding all your LMB, then that number could really get expensive, and spread the benefits of trout to LMB that may not make the final cut anyway.
IMO, you've done everything correctly so far, so I would stay the course until your particular situation changes, or your LMB are large enough to specifically target for increased forage. At that point, feed them until they waddle in the water. I bet that point gets here pretty quickly for you.
Just my 2 cents.
