You know you don't HAVE to watch them, right? If you don't want more Saw sequels, then just don't watch them. It's pretty simple. You're probably not going to like Saw 3, you already know the ending of the movie, and knowing the ending of a Saw movie before you see it pretty much spoils the entire movie. But yeah, Saw 3 has more character development than Saw 2, so you're probably going to like the characters.

I didn't see any flaws in Saw 2, please elaborate.

I like Saw 1 and 2, but Saw 3 was way too gory for me. It could've saved itself on some of the gore and concentrated more on the psychological part. I don't really see how Jigsaw could've predicted how everything near the end would happen either, seems a bit far fetched.