The YP are going to be hard to get established in a LMB pond. The LMB like them more than BG. In regards to the BG, sounds like you need more recruitment of them to keep up with the LMB. I would concentrate on supplying the right habitat to make that happen.
The LMB shouldn't be that hard to thin out with some fishing, if you didn't want to go the musky route. Once the LMB start getting less in numbers, some of them will be able to start finding their needed forage, and some of that will be their own, which helps you out more in thinning.
