Interesting thought....
Has anyone tried a remote power steered Minn Kota motor in a river application?
Since the power steering feature is only available in the bow-mount versions you'd have to design some sort of bracket to mount in on the transom. The little experience I've had with using a small 27lb thrust motor on my driftboat makes me think it might be a little tricky to controll a boat in current with the power steer feature. The power steer feature would need to react pretty fast.

I see on their website that Minn Kota now makes a co-pilot remote control steering gadget that allows you to steer the motor from anywhere in the boat with a hand held remote.