Kunis was the worst one - totally miscast. Did you believe she and Rachel Weisz were sisters?
Severely lacking the feeling of friendship and personal journey that the characters in Wizard of Oz had. Over-reliance on cgi characters, can't they get midgets to dress up like the old days?
This has Star Wars prequel type issues - no heart, all about the look and the 3D effect.
Sums up my feelings towards it pretty well. Major pacing problems - could easily have trimmed half an hour out of it. It had none of the charm and humanity of The Wizard of Oz
and, as you say, was overly reliant on CGI and noisy special effects.
The cast were all pretty abysmal. It's all very well casting TV actors like Mila Kunis in order to get the kids in but they don't have the talent to carry big screen films. Franco was entirely unconvincing but with such a poor script, Robert Downey Jr had a lucky escape by not taking the role.
Very disappointing film. Go and see In The House to see how a director tells a story.