I don't think that we'll ever see just Kurama fighting the way that the eight tails fights. Because like Yazen already said, they work together in different ways. I think other than Naruto merging Kurama's and nature chakra together there's not much else for them to do, there isn't really a point in having Naruto turn into a full bodied Kurama. I mean, look at this chapter, he basically has all of the ninetails powers in this current form. He's big and strong enough to fight on par with five of the other beasts at once, even though he is getting help from the eight tails, and now he's about to use the bijuu ball. The only drawback to how they are now, is that there's a time limit. And Kurama himself said that that was only because it was their first time merging and it wasn't perfect.