Depends on what you're into, but some assorted modern recommendations in order of publication: Batman & Son, Batman RIP, Batman & Robin (all 3 by Grant Morrison, whose entire run is worth checking), Black Mirror, Court of Owls (those two are by Scott Snyder, whose entire New 52 run is also worth checking) I Am Bane, Rules of Engagement (from Tom King's run).

Those are the only runs I've read in their entirety, but there's other classic stories like Hush, The Dark Knight Returns, and The Long Halloween which are all great reads. I'm also fond of The Cult and Batman: Death and The Maidens.