Shame is if this connected universe thing wasn't happening, an older Batman trilogy would've been awesome. I really liked Bruce's arc in BvS and I don't think that'd work with a younger Batman.
I feel my ideal scenario is for The Batman to be like Godfather 2, interconnecting a flashback with the present story, except all centered on Bruce. So you'd have Affleck as Bruce in his 50s and Armie Hammer as Bruce in his late 20s. And the story hook is something from 25 years ago connecting to a current case.
Plus it'd be cool to see Batman in the 90s, early 2000s evoking Seven and the like.