I think the documentation under https://yunohost.org is very good. But in bad structure… It’s hard to find the real information
e.g.: “What is YunoHost?” is very good: YunoHost • index
But it’s too much hidden. Like many other good sites. Probably people do not find that.
Think this page should be seen if you scroll down.
IMHO the homepage is nice for mobile surfing. But bad for normal desktop browser. Think a main navigation is missing and the JavaScript only “back” function is broken, if you open links in tabs.