Im running the same transducer you have. I primarily troll lake erie and ontario. When doing so the chirp transducer is really good. for the most part i just leave it on the "auto" setting and let the computer choose the power and frequency it deems appropriate.
However, when Im targeting Kings on Ontario out in deep water....like 150-250 down in 500fow I do adjust the frequency and power manually to zero in on the target depth I'm fishing.
I don't find the side scan useful at all on the great lakes trolling for walleye, steel, browns, kings, lakers, etc. However I DO find it a bit useful when I'm on Chautauqua lake going for small mouth bass. Theres not much structure down there, but you can find some.
I was hoping that I could use the side scan to pick up my dipsys, copper rods, lead core out on the sides running off the planer boards. But either I can't decipher what I'm seeing on the display...or its just not able to perform how I want it to.