Bale is a fantastic actor...
He was easily one of my least favorite Batman. His animalistic, shouting voice was so misguided ... heath is the only reason people really recognize those movies as anything significant. This is coming from a huge nolan fan... those movies were expositional disasters and bale has come forward even stating his Batman disappointed him...
Affleck in many peoples minds is a subpar actor at best yet nailed bruce and batman.. had he been in better films he would be hard to surpas...
As far Roberts physic the reality is 3 months is likely all he'd need to have muscle and be defined. At least as far as looking athletic. And if he never takes his shirt off then we will never know regardless.
Personally more muscle is better. But if a keaton esque defining performancing and a fantastic movie comes out of this... then I'll be happy regardless ... plus photos have surfaced of him packing on muscle... so he may just be taunting easily angered fan boys... most of which are pretty tubby