Joke answer? I would die of shock the moment I heard the news confirmed.
Real answer? It or anything like just won't happen. QT has made it clear he won't inflict HIS versions of our beloved comic book super heroes on us cuz, frankly, he doesn't need to add our collective whining onto his list of things he has to ignore while trying to be a successful Hollywood filmmaker. And I respect that. I find little to criticize. The man is just saying he doesn't think he'd produce a crowd pleasing and financially solid film for both the fans and the companies that own these characters. He needs lots of creative control when he works on a project and he would feel constrained by the obvious interests of the studios involved or by the need to color so inside the lines that we as fans these days kind of expect and require from those making these films. The great wailing and gnashing of teeth you hear coming from the FF threads since that fan base learned what is going on with Trank's reboot? Yeah... That would be a walk in the park compared to what we'd be in for if QT were handed the keys to something like SUPERMAN/BATMAN or AVENGERS.
I suspect, unless it were filmed over seas for the majority of it's shoot, that such a theoretical film would be a boon to rumor/gossip sites. I could see daily battles with the studio and the fan base with every single piece of news to come out. Look at how he has cast his films... Do we really think that we wouldn't get multiple Jordan/Teller/Eisenberg style casting decisions from QT? That's by no means a judgement on my part on the cast of Trank's FF or Jesse as Luthor at all. I'm just pointing out that the fans have a specific vision they want and expect to see with every franchise from the studios and Zod can they be vocal. We did let these studios get a little creative, and were more lenient on changes earlier in this modern age of CBMs (Does anyone think that the reaction to organic web shooters in Raimi's films would be BETTER with today's fanboy audience if it were to be introduced today rather than in 2002? ) but now we've been through Avengers- mania and TDKT. We have all seen the Affleck and Jordan casting reactions. Does anyone here think that QT's vision of your favorite character would line up enough with your own for you to NOT scream bloody murder? Think on that real hard, not to mention, we are talking about a guy more than willing to carve up and re-write and alter his own passion projects if he feels things aren't working in going from page to screen. He's sanguine by nature I think. I doubt he quite share's our precious attachment to decades worth of continuity and "the essence" of these characters. Now, maybe these indeed would be great or thought provoking changes, or at least in the context of a stand alone CBM very interesting and off the beaten path but entertaining. But we would be more receptive of him doing that with the likes of The Thunderbots or The Suicide Squad. For Superman? Batman? Spidey? Cap? Sorry. The last few years has shown that we aren't and the mass audience aren't looking for a huge reinvention of the wheel here (and before people start waving around GOTG, be advised that I've been immune to that film's supposedly "risky" charm from about the giddy up. GOTG was in execution, plot characters and even SFX so by the numbers to me that I think if you left your w-2's in the same room with the Blu-Ray for a day I suspect that when you got back home your Federal and State tax returns would have magically been filed without one human hand touching anything) and that there would be a crap metric ton of resistance here and elsewhere in fan land, and a nice chunk of that would filter up to the GA.
So, no, I wouldn't want to see Quentin do BvS for his sake and ours. As a film maker from QT I want 100% of his Tarantino goodness, not compromised to any extent. As a super hero fan I am not blind to the necessity of change when adapting things for the big screen, but my gut tells me QT would make such size able changes to a given character and his story that no matter how good the film was I'd probably still want to see and prefer a version more in line with what I have in my mind about any particular character, story or plot element used in the film. Any way, the genres I NEED to see him tackle before he retires or dies are Supernatural Horror, Sci fi, a full blown ensemble gonzo comedy and believe it or not, a romance.