I'd first like to see a successful series of batman movies that show us a big part of Bruce's life, adventures and villains, and then a Beyond film. Having it now would feel like getting beyond after 3 episodes of BTAS.
Sure in the future, some bat movie is going to be crap, but the same happens to bond. Ignore it, dont let it take the franchise down, and come back with a better sequel. Keep the continuity and show us Bruce evolve as a character throughout the years.
Then we can have a Beyond film that makes sense. By the time we've had a few more batman movies to give us a more complete view on Bruce's life, Bale will have gotten old. Maybe not old enough, but maybe he could play grumpy old Bruce. It would be perfect!