Also keep in mind the fact that Kakashi was selected to be the 6th Hokage in Konoha, which actually, compared to other ninja villages has an abundance of notable/good ninja. I mean if he was head of Sunagakure where the only notable ninjas are Gaara and his siblings then it would be considerably different.
He was also *somewhat* nominated against Danzo who we know is incredibly powerful and was able to go toe-to-toe with MS Sasuke, without being able to use KA or Shisui's eye in general, and having to hold back in case Obito was there. THAT along with Karin (who is actually fairly intelligent) was observing Izanagi for Sasuke's sake.
He also took precedence over Gai, who we know could be lower/mid-kage level (and for you "only with gates" people, yes of course, but it is still his ability).
And technically, he took precedence over Naruto too, considering Naruto is basically the strongest ninja that belongs to Konoha at the moment (Sasuke hasn't officially been accepted as back). Villagers were putting support for Naruto as Hokage.
Kirigakure only really has Mei and Ao...
Iwagakure has Oonoki and.. Dare I say it? Kitsuchi.
Kumogakure has Ay, Bee and possibly Darui.
The fact that Kakashi and Gai were able to go toe-to-toe with six-tailed beasts for a short while speaks wonders about them. They also had two jinchuuriki aiding them but then we have Mr. "I-Can't-Be-Touched" whose been planning this for about half of his life pulling the strings.
In spite of all that, he's a good ninja.
He also went up against Hidan and Kakuzu. Hidan is NOT fodder, but he's not exactly the strongest Akatsuki member. He's 2nd weakest to Zetsu in my opinion. After fighting Hidan (thus wasting a bit of chakra) he managed to put up a decent fight against Kakuzu.
And he also solo'ed Edo Haku and Zabuza AGAIN. Two ninjas who are about high jonin level that could make a possibly low-kage level combination.
All of this indicates that he is indeed, Kage-level.
