From my point of view, it is the best site for publishing and downloading indie games in a general purpose. I think even indie is an understatement because I've seen medium sized studios and companies publish stuff here.
Other sites have features or cons that you can't publish or play games that you can find on itch.io, there is everything here and they recommend great stuff. In my opinion, there is no better option at the moment. That doesn't mean it's perfect, but the staff seems to listen and act on the things that are said in the community, so the bad things have to be said so the site can improve.
Personally, I'd like the launcher to be little by little more " cool" like the Steam or GOG launcher. It's not bad but the way it navigates and uses it feels dry and very 'to the point'. In the future the launcher could be redesigned to make it more attractive and varied.