Interesting, thanks for the feedback also as it shows different groups as well. Interestingly I had done the same with a few people who I built PC's for and offered W7 or W10 and they had a try on a dual boot PC I had and said they didn't care as long as it worked. Both have a start menu, desktop icons, search function and internet and work with basic programs fine and that is all they were worried about. Navigation has zero difference in premise and the start menu with the small tiled icons most preferred as they found it visually easier to find what they wanted.
I just left them with default config for start menu, Windows 10's start menu can be significantly improved with light tweaking - it could and should be a significant strength for 10 but they have crippled it by trying to push a specific style rather than exploiting the potential (i.e. more like Android launcher in respect to customisation options both as a menu or screen and with proper group management, etc.)
I think one factor is that the default Windows look with the smoothness and bevels, etc. gives 7 a friendlier look (some of these people are almost afraid to move the mouse incase they break something) while 10 has a colder more serious look. I hope they adopt a Zune alike theme system wide atleast as an option as I quite liked that on XP and the default 10 one is aesthetically gash.