Hi a lovely part of the country and have some fond memories of visiting when in my late teens but my wife might read this so won’t go into details
Some good access to the water around you as well.
Perhaps have a look at the Boat world range, Excel, or Honwave for starters.
Can only speak for the Excel Volaire and although capable, far too big for one from the boot, and need a good sized ob to move it.
Outboard I would think under 10hp for weight or maybe even a 6hp, but still a bit of power to get you out of trouble.
A Frib is another option if you YouTube Donny Wilcox you can see with his knowledge, what it can do.
He coincidently spends a lot of time out with kayakers, so he might be a good contact for you in the area, if don’t already know of him.