Predictability and conventionality is not a bad thing for most narratives. Actually, it means you're doing a few things right. It means you've built up a universe with a logic and system of rules that determine a story's future based on the events of its past. There are only so many possibilities in the limited range of any given characters' choices that won't warp the creator's ultimate vision. All the pieces matter. Look at it like a jigsaw puzzle. Once you've got 95% of the pieces in place, it's pretty obvious what shapes the final few are going to be.
Breaking Bad doesn't fall in the realm of fantasy or sci-fi or other heavily stylized genres. Despite seeming a bit surreal at times, the world of Breaking Bad is based almost entirely on our own world. And in just about any modern society, there's only a handful of possible endings for a story like Walt's, for the stories of everyone he's corrupted. Anyone with a few years of experience living in modern society could put together a rough outline of Walt's inevitable downfall and the disintegration of his drug empire. Sure, the fine details still require creative input and need to be imagined to a greater degree in order to be written, but I'm sure a lot of those have yet to be revealed, that they will flavor the remaining four episodes, and that they will shatter any perception of Breaking Bad succumbing to cliche during its final chapter.
I get a little irritated when predictability is associated with bad storytelling. That might not have been anyone's intent here, so I'm sorry if I'm just ranting for no real reason. Suspense is not necessarily a result of not knowing what will happen. It can just as easily result from knowing what will happen, too. When you identify with or care about or have any reaction whatsoever to a character in a story, suspense emerges as a dissonance between what you think that character might deserve or want and what few possible logical outcomes actually remain. It's probably a different kind of a suspense, or maybe it's not suspense at all, since it seems like a silly argument to make about the feelings a viewer might experience in response to a work of drama. I guess point I'm trying to make is that a drama doesn't require the narration to conceal information from the audience or resort to bizarre plot twists or hide future events behind unforeseeable chaos in order to inspire feelings of suspense.