In light of the recent GKMC discussion I recently discussed and argued in favor of the album's greatness on another forum. Here's a short blurb from what I wrote:
Just so people don't think I'm talking out of my ass or just trying to be contrarian. I definitely think GKMC is quite cohesive, and don't believe in this sort of weighted outlook on sonic cohesion vs story driven cohesion. GKMC is a story of growth, it starts out with this sort of adolescent outlook on life and tells the tale of religious and spiritual redemption and the subsequent ascension of success that followed Kendrick. And this growth is very well integrated into the very fabric of the album, which is why you have these somewhat big dynamic changes in the sound like the Backseat Freestyle, which portrays Kendrick at the height of his immaturity and ignorance. The abrupt transition from Good Kid to Maad City captures Kendrick's spiritual change from glorifying the gangsta culture that surrounded him to being horrified by it. The brilliance of a song like Sing About Me, Dying of Thirst can not really be overstated. It features an epic tale in of itself. Within the song, Kendrick raps from the perspective of all of these different people throughout his life whom died without redemption or "of thirst". And the song is quite moving and extremely well nuanced with little attentions to detail like Kendrick's slight change in cadence and tone to represent each persona and having his voice kind of fade off at one point to represent their untimely death. The closer Compton perfectly encapsulates Kendrick's meteoric rise out of the ashes of the imporverished and crime-ridden streets of LA. GKMC manages to pay homage to the history of urban West-Coast culture while also being able to sort of transcend it musically.
...Having the b-sides and bonus tracks Black Boy Fly, The Recipe, and Cartoons & Cereal definitely elevates the album quite a bit too.