Leo's performance was enjoyable, but not an award winning one at all. I think Jonah's was better.
I have seen all of the above movies... 12 years a slave is the only one that I didn't think lived up to the hype. I don't wanna seem out of line, but basically any well made movie that deals with race issues is going to be "critically acclaimed." Then add Brad Pitt as an executive producer, and your film is in a win win situation. Imagine if Quinton Terrantino made a film about something like the Holocaust. Not to be insensitive, but it would be up for picture of year...for sure...
I doubt if Tarrantino made a film about the holocaust it would be critically acclaimed in the way 12 Years was. He did make Django Unchained remember.