On the subject of CGI - We have crossed the barrier of what looks real and what doesn't with Gollum in the Rings films. But the real problem is that our minds have mapped what looks real physically and what doesn't. If the really super rendered character does a move that is not right on in the world of real physics, then your mind will say, "Wait! what was that?". There are many moments in otherwise perfectly done CGI scenes that get that subconscious reaction, and it can take you out of the flow of the scene - just for a moment - but that moment will linger in your mind long enough for you to actually think about it, which impacts the scene in an adverse way. Examples are few, but painfully obvious. One is at the end of Jurassic Park when the characters are running out of the rotunda as the T-Rex attacks the Velociraptor and the T-Rex tail pass behind a background object for just, maybe, 3 frames. You say, no big deal, but your sense of what is right and normal flashes the red light, and you are off the track of the flow of the climax of the film, if for only a split second.