[wwweston]

It's definitely a show that unfolds in a lot of directions and that doesn't make it easy to zero in on a predictable narrative. Personally, I like that it managed to do that -- while still actually having a narrative arc and sense the writers had done their homework, unlike, say, Lost and Twin Peaks, which are probably two reasonable analogues.

Also, like a lot of character dramas, the most direct "about" is your investment in what happens to/between the characters. But I think you could fairly say the show is an exploration of how we come to grips with limited control over our minds and emotions.

[JansjoFromIkea]

An even closer one would be the Leftovers seeing as it shares a few key crew members (well, Theroux and the lead writer worked on the Leftovers, at least).

The Leftovers was basically Lost done right, very very clear from the onset that it's about people's reactions to the craziness than the underlying reasons for it. Maniac feels like it has some unnecessary stuff tacked on, the premise has a Charlie Kaufman copycat element to it all that feels like a necessary gimmick as opposed to something which naturally fits into the world.