Regarding the fins, it’s still too much, but it’s individual.
My 5.20 kayak turns easier than the SUP, although that was my first impression. And, in fact, the first way out. I recently got on smooth water, I prefer mountains, a stormy stream, high speed.
But my soul constantly asked for water, and the Caucasus and the Carpathians are available to me once a year, no more. So I switched to smooth water, and now I’m hooked

As for my SUP, I oriented it towards hikes of 3-4 days to begin with, with full autonomy, i.e. the whole bivouac is on the board, food, water too.
In principle, in the spring, as I polish, I plan to do 140 km along the Desna, go out for 3 days, maybe in May, I want to pull people up, ask for a canoe, which I made to order, I have 3 kayaks now and go for a walk.


As for operation, yes, there are limitations, but not as big as it might seem initially.
With my kayak, after the first year of operation, both in good wind and waves, and, accordingly, a jib in one place, and among the ice (I had to break the ice in December before last to get through the river), at most a couple of scratches on the varnish.

When I was at the Red Bull Marathon, I had to get off mid-distance, my legs cramped and I completely lost control, while starting I took in more water. In general, I found a place to drag the kayak up the slope, then until I got to the people with the kayak where there was still water splashing that I couldn’t pour out, who were able to explain “where I am” to the driver... Why am I doing all this? Besides, I dragged the kayak behind me for 500 - 700 meters, along the ground, roots, sand. branches. Not a single mark on the varnish! But the varnish is not very cheap
The second kayak capsized on Mezhtgorye and the man, with a good wave, simply dragged it onto the concrete pier, tried to get into it 2 times and capsized and everything repeated. There YES! 2 layers of fiberglass were pierced, and not all the way to the wood. It was possible to continue.

I do the same thing on SUP, it’s hard to kill.
He is not afraid of the sun, and in winter he can lie in the snow in any frost.

As for sharp stones, I don’t take small pebbles from the sea, they don’t leave marks, just like shells, then yes, stones are deplorable for him.
If you run it over asphalt, the coating will also be 100% damaged, and this is not fatal, it is a loss of aesthetics. no more.
But everything else does virtually no harm. Including falls from a meter height.

In any case, the kayak had nothing, and I mocked them to the fullest.
As for repairs, everything is much simpler, including the possibility of carrying out repairs while traveling.

Regarding foam mats, in my case this is not an option, or I have not yet seen mats made of transparent foam. I don't want to close the drawing.

One more thing, for me a tree is a soul, its own character, exclusiveness.
As for mass production, this is a serial production.
But this is my personal opinion, on which I do not insist