My faving system work a bit like a bookmark. I usually fave one pic of an artist that i discover and like, so i may find them quickly in my faves list, which is much more visual than the watch (friends) list, or any folders that i might save their work in. That is of course, in case i forget their profile name, and i need a visual remainder. The popularity does not matter one bit. : D
I have on occasion not faved something because it was already hugely popular, I instead go to their site and see if there's other pics I like in there. I guess sometimes it's just that I don't want to jump on the band wagon, and other times it's because I didn't necessarily like it all that much but my first instinct was to fave it because so many others like it.
Nope! I am a little bonkas with faves. I fave A LOT. Simply because there is so much amazing art here on dA! And I love setting my favourites to random, and looking at them whenever I glance at my profile!
I won't avoid faving an artwork if I really do like it. My faves are for me to keep track of stuff I like so who cares if other people like it too? I would only avoid faving it if the artist had an attitude problem, like those people who would post an artwork and allow comments and garner all the faves but refuse to acknowledge the support of others and act like they're way above everyone else.
...however, I tend to prefer commenting on pieces with a low comment to favourite ratio. Unfortunately I'm one of those people who don't usually comment if there are already tons of them out of fear of bugging the artist. What I may have to say must have been said dozens of times, and I don't want to pester them ;; I'm pretty shitty when it comes to writing meaningful comments, haha. Of course, there are exceptions where I can't help myself.
But I realize how disappointing it is to get tons of favourites and no comments. I appreciate when people favourite my work, but it's always nice to start a conversation or something with someone because they took the time to comment <3