Darklone said:
Now take the stats as by the normal point buy and you'll have the halforc with str 18 and the human with str 16. Much bigger difference.
Well, our group doesn't use point buy or arrays, so I do often forget about the impact they can have (BTW, I'm not quite sure how would the point buy for the 1/2 orc and human differ ?)...
But anyway, lets see:
A.) 1st lvl 1/2 Orc Barb, 18 STR (22 while raging), Power Attack; greatsword
B.) 1st lvl Human Barb, 16 STR (20 while raging), Power Attack, Cleave (human bonus feat); greatsword
While raging, A strikes at +7, +6 if using PA, and hits for 2d6+9 (2d6+11 for PA).
Same situation, B strikes at +6, +5 if using PA, and hits for 2d6+7 (2d6 +9 for PA).
So, yes, indeed, the 1/2 Orc averages 2 points per hit more damage. I personally don't consider this game-breaking, or even deserving of an extra -2 to a stat. Throw in the Human's bonus feat (Cleave), all of a sudden the Human is potentially averaging a LOT more damage per round.
If you try hard enough, you can point out a situation where any stat outshines others. I don't think Strength is inherently a better ability to get a bonus on than others. If anything in the above examples, I think there is more of a problem with how Power Attack and two-handed fighting rules work than any stat bonuses.