That assumes Warner Bros. is interested in investing in new visual effects. I've seen nothing indicative of that over the past decade.
Also, for what you propose, the original film elements would need to still exist (in order to redo any effects combined with live action -- not an insignificant number of shots). Now, I believe that is the case (although some instances, such as rats eating original elements of "The Gathering," are not promising), but who knows how long that will continue to be true?
I'd purchase what you propose in a heartbeat -- but it seems, at present, unlikely. In lieu of that, a 4:3 version (which would look far better, since the effects wouldn't be crappy due to cropping and zooming) would be preferable to the versions that exist in wide circulation at the moment, and take a far smaller investment from Warner Bros. But, it too, is unlikely.