Jon Bernthal, Michael Rooker, and David Morrissey are awesome actors. There should be a lot more "bad" people on the show. They're phenomenally more interesting and well-written than the central "good" guys.
The trend I see is that the good guys keep doing things that frustrate us: go crazy seeing visions of dead wives; mess around with walkers and cause them to kill guys named Dale; mope around and keep on ruining people's hopes of her hooking up with Daryl; deny the governor's craziness and sleeping with him; spontaneously sing songs at the most silent, random, awkward moments; etc.
Even Daryl and Michonne aren't so interesting (I dare say it) when you compare what Shane, Merle, and Philip all went through plotwise. Daryl and Michonne kind of just show up and are awesome from the beginning, but they don't get much evolution or buildup. Daryl appears dirty and haggardly with a bunch of squirrels and a crossbow, and Michonne slices off a zombie's head with a katana, cloaked, with two mutilated walkers chained to her. Or maybe that's why we like them: they are whom they have been from the beginning, and we admire their stability and badassery, or we have some sort of wish fulfillment thing going on

.
Anyway, this season is awesome. So much stuff going on, even the comics can't keep up with this. I bet the boring episodes would've been less boring if there hadn't been a week of waiting before and after them; in hindsight, however, everything is cutting together nicely.