Honestly, I'll be happy to be proven wrong and even if not, I'm certainly curious to see what this could become, but I have to agree Tarantino is about the worst possible fit for the franchise I could imagine.
The violence is jarring enough, if he maintains his usual style (and no, TWoK does not compare even slightly), but that's not even the major issue. The real problem is that anytime I watch a Tarantino movie - entertaining and well-made as they are - what I'm looking at is about as close a thing as I can imagine to what I would consider 'Anti-trek'. Hateful Eight, Inglorious Basterds, Kill BIll, Reservoir Dogs, Django Unchained, Pulp Fiction... These are movies about bad people. And not just people who happen to be bad, but movies where all people are bad, just to varying degrees. Even the purest, noblest heroes he makes are violent psychopaths driven by revenge. I have literally never felt an ounce of hope or optimism of any kind anywhere in his movies. Usually, they seem pretty much designed to make you weep for the human race in general. That's not a bad thing by itself, but it certainly doesn't fit in the world of the Federation at all.
Obviously, he isn't confined to only doing what he's done before. But he has been following basically the same lines in every movie he's made (that I've seen) so I don't see how we can just assume he won't do the same, here, (especially with the news that he insisted on the R rating).