Allow me to drop some classy rappers on you simpletons. Also, this is a decent list you should all go by. Excuse some of the biasness to my specific taste. These are in no specific order (except by the tiers).
God Tier
Danny Brown
Tyler, the Creator
Nas
Serengeti
Busdriver
Deltron 3030
A Tribe Called Quest
Pharrell
Tupac Shakur
Biggie Smalls
Kendrick Lamar
Mos Def
MF DOOM
Average Tier
Common
ASAP Rocky
Kanye West
The rest of OFWGKTA
Pusha T
Jay-Z
Schoolboy Q
'Meh' Tier
Lil Wayne
Kreayshawn
Lil B
Chiddy Bang
Das Racist
Rockie Fresh
Wiz Khalifa
Wale
God Tier - The definition of rap music. The past, present, and future best in the industry, and the future of the genre whether you like it or not. You should have at least one album or mixtape from any of these artists.
Average Tier - Pretty good, normal stuff to listen to, decent lyrical content and they each have a unique style.
'Meh' Tier - You can listen to them for pure entertainment. They aren't very awful rappers, but they do not deserve to be put any where near the God Tier artists. (No, I did not make a mistake, Lil Wayne is not all that. The only reason he is even on this list is because of his previous stuff with Da Drought and the first Carter. Most everything else after Carter II is mostly trash).
List could probably go on, but this is basically off the top of my head.