While looking at the PF Barbarian I realized that effects like the Extended Rage feat and the weapon special ability Brash don't really mesh well with Pathfinder rules. These two effects extend the duration of a Barbarian's rage by 5 and 3 rounds respectively.
The issue arises when we take into account how the two different barbarians use their rage ability. The DnD Barbarian can only enter Rage a certain number of times per day, while the PF Barbarian is allowed to use their Rage a certain number of rounds per day but enter it as often as they want, even just using 1 round of rage at a time if they want to.
So how exactly do Rage extending effects affect a PF Barbarian's rage? Would you add 5 to the total number of rounds they can rage in a day with Extended Rage? (Which makes the feat underpowered.) Or, would you add 5 to the number of rounds they can rage each time they enter rage?(Which would give them essentially infinite rounds of Rage per day, provided they never used it for more than 5 rounds at a time)
I do realize there is a PF feat, Extra Rage, but it only adds 6 rounds per day which makes it significantly weaker (which seems rather unusual) than its DnD counterpart at later levels.
I didn't see anything in the House Rules section that addressed this issue.
I do have one suggestion: Alter rage extending effects so that they are +X rounds per day +X additional rounds for every 4 Barbarian levels they possess. This keeps it in line with the number of times per day a DnD Barbarian is allowed to rage.
Example:Extended Rage
(This article raises further questions about the Frenzied Berserker PrC. I think I'll work on converting it to a version compatible with the PF Barbarian and throw it in the Requests section.)