but not sure if I'm ready to hear how my "fly by the seat of my pants" pond non-management favors?

I had a pond dug approx. 11 years ago (1 acre with the deepest depth 21 feet & average 10 feet depth) and feel ashamed for the following info:
I stocked BG, LMB, Crappie & White Amurs. All, but the white amurs, were just caught from local ponds and dumped into mine. No counts and all sizes with the largest LMB at 5 lbs.

I have a windmill aerator and a fountain for circulation.

Throughout the years I've caught nice fat LMB, Crappie & BG. Lots of BG and LMB nests and fry. Last year I started catching long but very skinny LMB. The LMB, 12" and under, look healthy. So, I built a holding pen in hopes to raise Golden Shiners in and release over structure. They are spawning now in the company of bull frog tadpoles. Hoping, eventually, they will multiply on their own (outside of the pen) and feed my starving LMB.

I since found this site and realize that I'm lost. I read here that Golden shiners can take over a pond! Should I be concerned? Is there another reason my larger LMB look as they do? Will these tadpoles screw up my Golden Shiners pen? Thanks