It depends entirely on the story, really.
My chapters vary in length, because I make them as long as they need to be. I try to pace stuff after what happens, rather than how many pages they take up - so some chapters end up being 33 pages, and other chapters end up being 17. I COULD pad out the 17-page chapter to make it longer - but why should I?
Drawing out scenes longer than they need to be is something I have to struggle with as well. It's probably the heavy manga influence - where the stories are generally slower-paced, with lots of space for atmosphere (which is is nice, if you can pull it off well!) - but I have a tendency to slow things down. To counter this, I storyboard meticulously, and try to fight against the urge to drag things out - if I can tell a plotpoint in one page, I probably should. Aim for the least amount of pages you need to get the story across.
Perhaps the guy who did the 12-page arc has found a way to condense his story and cut down on length. Perhaps he had a less complex story to tell, thus requiring fewer pages. Knowing nothing about your story, I can't tell you if 16 pages is too much or too little.
Don't measure your page-count against what other people are doing - measure it against what your story needs.