Fans enjoyed the first two seasons. Critics and fans enjoyed Children of Earth.

Everyone hated Season 4.

I personally hated season 3 and 4 and found them to very light story wise and thought the first 2 seasons when torchwood was at it best, when they focus on 1 story an episode.
Russell T Davis write best when he only has to think about a single episode or two at the most.

In my book Jane just not that good of a writer in today world, may be she was good back when she was doing Buffy the Vampire but she certainly not good in today world, when you have excellent writers of Lost and Fringe as competition..