He, like no other, popularized the celebration of B-movies, pop culture, violence, style, and genre movies. geeks became cool all of a sudden. Who else was there, besides the Internet, who did for film geeks what he did for us? There's even a sitcom about geeks now. you see I use "us" because I see myself as a massive geek. I'm neither an Average Joe, nor a film snob.
And I am not overly concerned with how these two groups see him. His legacy, will hopefully be that of a man who did what I wrote in my first sentence in this post.
QT should not change what he is doing one bit, just because most people, including of course Average Joes and critics, do not understand him, doubt him, or even hate him.
To tell you the truth I am astouned (and at the same time extremely happy) that there is a market for QT movie in todays world. Because mainstream Hollywood, aside from some excellent exceptions, sucks pretty hard atm, and the zeitgeist is pretty weak imo.
Again, there is this being overconcerned with "leaving his mark in film history", the legacy, etc. etc. Movies should not be judged by how much influence they have/had. And this is why I don't think Citizen Kane is the best movie ever, it's NOT, and the AFI can suck it with their stupid lists.