Analysis of Dangerous Strikes should also consider secondary benefits from the crit. In particular, the berserker's Furious Critical feature makes this tempting. Now you're not just getting a tiny bit of extra damage (on average), but an extra chance at a fear effect, knockback, knockdown (advantage), or just flat out extra attacks which themselves can trigger extra attacks. (Or various other effects.)
I've had to do my own rethink of maneuvers for my barbarian -> berserker conversion, because my preferred weapon (glaive) is not a heavy weapon anymore. That immediately removes the majority of the Adamant Mountain school.
If you look through the 1st degree maneuvers, there's actually almost nothing available as an action to improve your damage output. The only option I see from a quick scan is the 2 point Cleaving Swing from Adamant Mountain, which requires a heavy weapon.
The Razor's Edge school seems focused on crit fishing, and it is not an unreasonable focus if you have options to capitalize on crits for more than just basic damage. Unfortunately I haven't seen much other than berserker that really takes advantage of that. Still, I could see a couple different concepts that would work when focused in that way, especially if you get extra BA and reaction attacks (eg: Polearm Savant, dual wielding, various reaction combat maneuvers, etc).
Of course my own character has leveled past the point where Dangerous Strikes would be useful. It would be largely supplanted by Perfect Edge Stance, if I went for the Razor's Edge school. I would probably take maneuvers with a different focus at low level, but I wouldn't consider it a bad option.