I see where you are going with this survey. About 5-10 years ago there was a short period of time when a soft ski boot was offered by by many boot makers. The had a short run because they were just too soft for most skiers. They probably would have been great for begininers but as rentals they were not sturdy enough to take the pounding that rentals go thru.
The best thing the soft boots did were make an outstanding little kids boot. I was lucky enough to have gotten them for my son when he was 2 thru 4 in different sizes. As an instructor I saw that they solved the problem that most kids boots are way too stiff for a little kid to flex them. If you can't flex your ankle it makes it very hard to ski well.
You want to design something - focus on a great kids learning boot. There is a big hole in the market down there.
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