You've got one really bad episode left, but aside from that and maybe a couple 'decent' eps, the back half of Season One is very solid. Episode 11 or 12 is, IMO, where the show really started to find its footing.
I watched the first season, and while I enjoyed it, it didn't really grab me enough to rush out and watch Season 2. I am definitely going to watch more of it eventually, though.
My biggest problem was with the number of standalone episodes. This is a show that I think would have benefited from shorter seasons with more arc-based storytelling. I really liked the main story, but I didn't like having to watch lots of unrelated stories in between.
I would definitely recommend trying it again. For the first four seasons, the show really gets better with each year, and the arc-based storytelling really starts to develop. Even in later seasons, when they did Monster of the Week episodes, they'd still find a way to develop something in a manner that works toward the overall arc.