When choosing a trolling rod, you need the following characteristics:
1) It needs a strong backbone. I would call the rod a fast taper rod – medium to medium heavy. It will have to hold the weight of not only crank baits, but Snap Weights, Off Shore planer boards, In-line weights and maybe Lead Core line.
2) It need a fighting tip. Trolling fish are often reeled in long distances. With a soft tip in the last 1/3 of the rod (again fast taper) you will land more of the fish that bite.
3) Long enough to spread lures. Spreading is done two ways, by putting the rods straight out in rod holders or by using in-line planer boards. For boards, we put our rod tips way up in the air so the line from the rod tip to the board does not hit the water. In our line of rods (Walleye Angler Signature Series) we have trolling rods ranging from 7’6″ to 8’6″ with telescopinig handles, as well as 10 & 12 footers that are 2 piece rods.
Of course add in durability, high quality components, and a reasonable price (cause eventually you will want a bunch of them) and you have a good trolling rod.