BAB: It's still way more than necessary. Pre-epic, I don't know of anything you'll be missing on higher than a 1 with a +40 bonus (which is easy to get with this class, as I demonstrated).

Mighty Blow: That's just a start in reducing the damage to reasonable levels.

Unstoppable Blows/Killing Blows: Drop it to a total of +3 to the multiplier (guaranteeing a x5) if it's really that important. Getting that at least 1/round is probably overkill, though.

Channeled Rage: Half would be much more balanced, I think. Still a nice boost, but not quite so amazing.

Two-Handed Savagery: That's the starting Strength. +5 from levels, +5 from a tome and +6 from an item puts him at 32; there was something else I was taking into account (Focused Rage, I think) that brought it up to 40.

Slay: The problem is that with all the crit-boosting abilities and static damage bonuses this class gets it's a standard action kill, 3/day. You can balance it by granting it later and not making it do crit damage on a successful save. Damage as if from a normal hit, sure. Maybe even half crit damage.
For reference, Finger of Death (a spell with the advantage of range but inferior in all other respects) comes at level 13.

Damage Preference: Of course there SHOULD be penalties, but saying "The DM has to figure this one out" is a pain for the DM. Does the bleed damage from multiple hits stack?
As for Bludgeoning: None of the debuffs on the first ability are given a duration, and there's not really much chance this class is gonna have less than a +40 bonus to hit, so making everything a touch attack isn't very powerful.
The reason the Dex damage on Piercing is a non-factor is because this class deals huge amounts of damage with little effort, so things will die before they get more than 3 or 4 points of Dex damage racked up.

Savage Frenzy: Flurry of Blows isn't very powerful because you can only use it when you're standing still. The same applies to this. It's powerful when you can use it, but it's difficult to use.

Surge of Rage: You get your choice of feats that are easily available at level 1 at level 16, at which point you probably have them if they're relevant to the character.
Another bonus feat is one of the last things this class needs.

Spirit Crushing Rage: This is a solid ability; it effectively locks down one enemy until they're attacked. I like it.

Perfected Rage: It's rather superfluous, with the bonus to damage the class gets.

I think the main abilities that need to get toned down or moved around are Unstoppable Blows, Killing Blows, Two-Handed Savagery and Slay. I still think it should use standard BAB progression (just for the sake of avoiding confusion).
Surge of Rage and Perfected Rage are mostly useless at the levels they're gained.
Savage Frenzy would still be balanced if you dropped the AC penalty a few points.