The second definition is subjectively based and comes from the reader. This is where words such as "fun" often come into play. For some, a comic might have to be about superheroes, for others, it could be anything and everything. The question is only worth considering by those putting out the book as it helps to have a determination of an audience. Sure, "all audiences" gets put out there as a hope, but never will there be any form of fiction that will be loved by all. So, artistically speaking, a creater has to determine what audience he wants to reach in order to determine what sort of product will be put out. 

I will circle back around to New Visions to explain this further. I am not the audience for New Visions even though I may find the stories enjoyable. Why? Because my subjective definition is based around an electronic format. Digital comics ultimately make me happier than printed comics. I'm not complaining. I'm not demanding NV be made available as a Kindle book (though I am quite surprised to see that Resistance is available on Amazon knowing how John feels, though I think it is a mistake as the desciption sounds VERY different from what I would expect in the book.) I think it is important that an artist create something that makes them happy. I go to a nice restaurant because i want to experience the work of the chef, not because I want to have it my way. Though, commercially speaking, we live in a world where an individual's singular definition of happiness will not be as successful as considering a larger audience. More options creates greater success. So I think its great when we have JB's New Visions right next to NuTrek comics. I think the only thing that could be better would be more variations of Star Trek comics on the shelves as there is no singular best way to have something done.   

For a much more elequent description towards my point, I turn you to Malcolm Gladwell as he explains happiness through diversity in spaghetti sauce, mustard, diet soda, and coffee.

https://www.youtube.com/watch?v=iIiAAhUeR6Y

Basically what Matt said above.

As for the description "graphic novel", I could except that if the format was a book with a paragraph or two of story per page with one picture on that page describing said paragraph(s). 

All the so called graphic novels I have seen are comic books.

Bandes dessinees when it's drawn stories.

We call it a roman-photo if it's the same thing with photos instead of being drawn. (Photo-novel)

plural: bandes dessinees

singular: roman-photo

plural: romans-photos

But ultimately any term with the word "novel" will never be legit until the owners of that word, the literati, accept it. Fat chance of that happening.