Well as you know Joe My boat Sea Barf is not exactly a jon boat but its nearly the same size. I epoxied a transducer directly to the inside bottom of my Livingston it shoots directly thru the hull with almost no signal loss. That lets me see my hummingbird depth sounder to watch all those fishies that drift under my keel.
For the electric motor if it didn’t come with them in the first place cut off those bolt on connectors and replace them with alligator clips for connecting the batteries much easier.
If I’m going to be alone in the boat I clip a short lanyard from my fishing vest over to one of the alligator clips so If I were to fall overboard the motor would stop.
You should also think up a catchy name for your favorite ride. To this end I meticulously and with great skill and care spray painted the name of the boat in blaze orange on both sides of the boat. Really snazzes it up!
One thing I did that really helps when you’re rowing down the lake is to have a large Truck mirror attached to the stern so you can see and avoid the other trollers coming from the other direction. This really saves your neck muscles from craning around to check the traffic.
Glue a marine carpet on the flooring of the boat to deaden sounds so as not to disturb sleeping carp or other fishy denizens of the deep.
I have a canvas catchall bag that attaches to the sidewall of the boat by velcro strips. It contains amongst other things a tube of graphite lube for the oarlocks. Nothing more annoying that squeaking your way down the lake hour after hour.
On the Transom I have mounted two wheels so when I turn the boat upside-down I can wheel it down to the lake with relative ease.
Glue a tape measure to each gunnel for measuring each fish.
Cup holders , need I say more.
50 cal Machine gun for people who troll across your bow.
I have a clamp on knot meter which is simply a weight dragging thru the water on a short line attached to a pointer on a knots per hour scale. Important for trolling for kokanee. 2.2 knots is optimum. Trout 2.2 or better.
For cheap effective anchors I use two iron 10 lb weights such as weight lifters use.
Anchor-line should be tied securely to the boat when you toss them overboard or you will have to find a flat rock to substitute like I had to at Stan Coffin lake when I tossed it all overboard and it quickly disappeared out of sight.
I use eye bolts instead of a pulley for the anchor rode to travel through as I have had the rope snag on the pulley more than once.
You can easily stand up in my boat so I can reach each end to set the anchors.
PS. Those Obus seat cushions with the heated massagers built into them will clip right on to the trolling motor battery. Caution their use can cause you to sleep right through bites.