I had twin Honda 40's on my 22 and just trolled on one of them In this case (of course), the steering was from the helm. This works fine for fishing and I managed to catch plenty of fish with that setup but it wasn't ideal to have to run back and forth to the helm - especially when single handed. However, on more than one occasion, I managed to back into the cabin to operate controls with a fish on the line. However, with this setup, the boat fished best with 3 people - 1 at the helm, one at a rod and one with a net. When we had a double and we weren't in a crowded fishery (e.g. plenty of space in front of me), I'd just leave it in gear and go back to net. I'd also troll down wind on windy days since it's impossible to keep the boat heading straight up wind without constant helm input.
If I were to do it again, I'd do a single and a 6-9hp kicker. However, I don't think I'd tie the kicker to the helm steering. I'd go with a TR-1 autopilot and hand held controller. If you have a good size fish on and it make a run sideways, it's nice to be able to turn away from it without going up to the helm. Single handed, big fish, kicker tied to the helm, sideways run = lost fish. If you can't afford the TR-1, I'd prefer a long handle on the kicker and manual control so I can deal with it from the cockpit.