Although I think that Kakashi is absolutely worthy of the title of Kage and is a such that level. There are things about kakashi that are not Kage level though.
1: Kakashi's stamina has been bashed about but let's look at the latest evidence. He is still going strong in the war and has fought & I can only assume beaten, many S-Class ninja. He is now fighting the Biju with Guy n Co and just used his shadow clone jutsu and then a lightning style chain. He has been fighting this whole time with the Sharingan active, so his stamina seems all too good, IMO.
2: Kakashi was elected for the title Hokage,twice.
3: Kakashi has awoken the Mangekyou Sharingan without even being of Uchiha decent.
4: Kakashi can use Rasengan, an S-class technique made by the 4th Hokage. He then infused the Rasengan with his own lightning Nature.
5: He is a bit lazy, his time-keeping sucks,he'd is quite immature and prefers to read sleezy books than do his work.
Other than number 5, I have listed many reasons why Kakashi is a suitable candidate for Kage. He is of course Kage level. But there are things about him that could be improved. Don't hate for no reason, make sure that if you have an opinion you can really back it up.