It looks to me like an Inglorious Basterds prequel. I'll say this about Tarantino, in relation to his films being less formulaic than your average Hollywood guff. He's full of contradictions.
They're not as unimaginative with their dialogue, characterisation, music, cinematography, structure, you name it, as most films with Samuel L Jackson or Leonardo Di Caprio tend to be. They're more dynamic, more entertaining. He seems to respect his audience enough to go above and beyond this tripe for them. But it's also the kind of indulgent self-worship which plays on a prejudice of his audience as blood-hungry attention-span-deficient bozos by saying, look how talented I am in that I can make you hold on longer than other directors before giving you your pay off. Watch me do this. In some ways, the virtuosity is refreshing, not to mention entertaining. A film-maker marching into multiplexes and titillating the action crowd not just with stylish violence but dialogue and characterisation and references from arthouse and obscure b-movies is cool. I wish it happened more. (Although when Guy Richie had the same idea, look how that turned out. And all the raft of movies post-Pulp Fiction that made you wish they'd just made a nuts-and-bolts thriller without all the jump-cuts, sub-Tarantino dialogue and non-linear narratives. It makes your realise how good Tarantino is when you see his imitators fall so far short.)
BUT Tarantino has his own formula for building a movie. This can also be tiresome, just like Adam Curtis can become tiresome, because the more of them you see, the more you feel the content is all just fuel for the director's showboat. They're a series of set-ups for him to show off, so it really doesn't matter if it's the holocaust or the slave trade being depicted. And I use 'depicted' in the loosest possible sense. Because they're all just costumes, sets and characters, which both revel in and (at their best) critique the nonsense of Hollywood portraying history.
On a more simple note, I find it hard to believe that Tarantino in any way intended for a movie to be racist. Not the guy who grew up in a black area of LA, and has worked with so many black actors, musicians, etc. He's probably too focused on making it flow well as a music video than to actually care about the content's themes. The fact that people are even discussing Django Unchained as having any kind of historical significance probably makes him laugh. He'd probably say to stop taking it too seriously, but take QUENTIN very seriously.