I honestly feel given that Batman Begins and Superman Returns cost each around 150 million and 200 million respectively that those sorts of budgets will NOT be sufficient for an epic scale JL film.
Criticalcasting, I totally agree with what you referenced in terms of needing to get Bale and Routh in this... it would be absolutely stupid to recast them as it would almost CHEAT viewers, as in they spent their money accepting a different actor for a particular hero but now to be given just another actor right after presumbably established and successful franchises would really be annoying. There'd be no slight continuity (one major thing the Batman movies suffered from)
What would the budget be for the film? Any idea for a potential storyline? There is no way this could involve Darkseid or some massive space invasion type of thing cuz that sort of stuff would cost more then 300 million, especially with all the powers needed to exhibit on display and interplanetary travel and war type scenarios and designing of ships and technology for the film.
Look at X-3, it had a budget of over 200 million yet although it had the most massive epic scale action sequence featured in an X-men film (which should've been featured in the first two films but those two films had **** action choreography courtesy of Singer, that sad, X-3 is awful), the action itself in the film wasn't so great with Wolverine hacking and slashing randomers, and Telekinetic cars being flipped over on fire over and over... i mean it was a great epic battle but if that's all they can do right now with 200 million dollars.... it's going to take a **** load more money to tackle Superman, Green Lantern, Wonder Woman, Batman, Flash, and Martian Manhunter each using his/her own powers and getting to a massive scale defence style battle against some alien invasion...
Presumably if they get a script, I've seen loads of casting posts but screw that... PICK YOUR CREW! if anything Crew is equally as important, who would you get to DIRECT, to Score the music, to be DOP (you need an abs fantastic DOP here), who would you get for Visual effects, make up, Costume designing... I'd like to hear it all from you folks