Welcome especially to another pond owner from MI!! This is great that there are few of us in MI meeting up here and sharing our experiences.

Can you please take picture and share with us what a 'white perch' is? I'm not sure we can give good advice without knowing what it is. I'm also not sure why you hate them or why the pond guy had a hard time identifying them as well.

Can you tell us more about how long the pond was there or how it was dug and stocked? Were you the person who stocked it? Do you feel there is enough forage food for the top end predators (what types of minnows do you have? Crayfish, etc)

Your solution for weeds again depends on what kind they are and how deep they are. If your shallows have american pond weed or curly pond weed or eel grass or other native and desirable weeds then you would want to keep them in place. If you have a type of weed that is considered 'nuisance' or 'invasive' like chara or eurasian milfoil then you may be better off spot treating in the northern pond. The southern pond that is choked full you may choose to treat the whole pool of water with fluridone. However treating a whole pond requires steady chemical levels for about a month so if you have inflow of water it may not work. I can't tell how the ponds connect in the picture or if there is a feeder creek, or if they are ground water/run off ponds only.

Feel free to share more pictures.