motor to rudder link
I have to have access to the motor since I don't have remote controls for starting/stopping/shifting or throttle. I often reach over the transom to manipulate the tiller arm on my outboard in really tight turns. I back into my dock, so the setting sun can shine on Mr. Mildew, just part of my never ending battle. I'm forced to make a 180 deg turn to do this and also must keep my mast out of the trees. At slow speeds and absent of high wind I can make almost "tank-turns" in the narrow waterway. I have unfortunately managed to impact the propeller with the rudder like this, Umm, not good. Backing down the rudder has a lot of force against it, Opps..But other than this I have found leaving the motor locked straight and steering via rudder is fine. It's very evident if the motor is slightly turned, I can't release the tiller for a second.
I wouldn't like the drag/resistance of a permanently attached link of my Honda to the rudder. My rudder is balanced (part of the surface is forward of the vertical axis line) and I "read" the resistance on the tiller by feel to determine if I have encountered shallow water, it kicks up and effort to steer is increased. I think it may also mask the signs of weather helm.
If your engine is tilted and the mount is lifted the prop should be well clear of the water when sailing, no need for full time linkage. I see this rig often on sport fish boats, linking the trolling motor to outdrive so th' Capt' can steer via his wheel.