revenge was a clusterfuck. It wanted to be an entertaining soap opera but failed to achieve that becoming a convoluted reset laden mess with a whole load of lame ass characters weighed down by yet another shadowy conspiracy. Yawn. Kelley can blame length of seasons all he wants but at the end of the day he just wasn't a good writer.
as for shorter sesons it means very little. True blood, Rubicon, burn notice, the killing, damages, Dallas 2.0, the following have or had short seasons and they sucked. Bates motel has been wobbly with a ten episode season
on the otherhand you had season one of heroes with twenty three episode season pulling off a near flawless season. Or tng with 26 ep seasons and managed in its middle years to be continuously good and x files seasons 1-5.