I doubt that burn-out will be that serious an issue. I used to get depressed a lot, until I learned how to hack the mechanism. With deep hooks into brain function, I see no reason why people would be depressed, unless they wanted to be.
Some will argue that heavily augmented people are no longer human. Back in the day, I'm sure that some considered the use of stone tools in the same way. But they apparently didn't have many descendants ;)
I use modafinil. I don't force 24 hour circadian cycle. And when I start feeling down, I laugh at myself for being such a dumbass. And that always puts a smile on my face :) Maybe sometimes it takes a few choruses of one Turbonegro song or another, or creative cursing, or whatever.
Some will argue that heavily augmented people are no longer human. Back in the day, I'm sure that some considered the use of stone tools in the same way. But they apparently didn't have many descendants ;)