I hate to be the snob but honestly everyone that's posted here so far with exception of NarutoB really has no idea wtf they are talking about when it comes to hip hop, even the OP's argument was weak. If you want to see where Tupac Lyrically stands amongst a small sample of other rappers, which is actually incomplete in terms of hip hop history's full roster of all time MC's, check this page.
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And broaden your horizons, Nas, Biggie, Kendrick Lamar, eminem, j cole are bland / generic examples. The underground has a tremendous amount of MC's that shit on Pac lyrically. If you want to know any reccommendations for great underground albums or groups just ask me, I know a lot about hip hop.