Which airframe/ outputs to control a skiff on clothesline mooring?

I’ve got a Carolina 16 skiff that I keep on a clothesline mooring in tidal waters. A clothesline mooring has a pulley on a pole on shore, and another on a pole offshore.
There are a couple of use cases I’d like to address:

  1. Keeping the boat perpendicular to the shore in wind and waves, particularly when loading and offloading.
  2. A mode where it would align parallel to the clothesline and then motor itself into shore. Likewise put itself back out to sea to its parking spot. My wife complains that it is hard for her to pull in and out in some weather conditions and she is right.
  3. Fully autonomous mission programmability. The cottage is on an island with no road and we often have to go fetch visitors about 5 minutes away by boat or one of us needs to go ashore therefore stranding the other without a boat. If it could take itself home that would be fine indeed.

My thoughts are to add a trolling motor next to the 40hp Yamaha and give it steering and thrust control as well as a mechanism to tip it up into storage position. Wireless control from the beach. For the first two use cases a simple keyfob with Zigbee/Xbee controller would be ideal as my wife would not be comfortable at all with an RC controller. For the self-driving mode simply drive it with a video link and RC controller.

I guess my questions regarding Pixhawk are:

  1. Is this a reasonable thing to ask of the system to do? Is there a simpler way to do it? At least for options 1 and 2?
  2. What airframe?
  3. What inputs/outputs and actuators would you use?

Thank you in advance
Jeff on Cedar Island, Clinton, CT