It's convenient to have an exterior on/off switch until you ship water over the deck on a rough day. My Mountfield 'Active' had just such a switch, and it died the day after getting very wet. >:( The replacement switch is inside now - for the couple of seconds it takes to get the superstructure off, well it could just save you a few hours buying and fitting a new switch, then filling the hole, repainting etc etc.
My Active has a similarly mounted towing hook, so I might follow your ideas for strengthening the mounting, though I've also added a sturdy set of bitts just aft of the superstructure. Tows well from them.
Andy