I'm just looking at this on core value (As I don't quite know what race exclusives there might be or what the feat rules might be for races), but the way I see it, the stat tradeoffs for some of the races are a tad odd.
For the first few races, the stat tradeoff is one of losing two points in a lesser proficient stat, which is probably according to role and conventional mindset.
The way this works is Tadeoff = giving up two stat points and gaining two stat points.
However, for some of the later ones, classes gain extra points in more areas, which turns the loadout into...
Abilities = (-2 In weak stat) + (2 in strong stat) + (Another two in strong stat).
The formula for half of them equals Race Bonus = (-2 stats) + (2 Stats) = Racial Focus
The latter becomes Race Bonus = (-2 Stats) + (4 Stats) = Racial Advantage.
This roughly translates into: "Hey, for the cost of two ability points I won't be using, I can four that I will be!".
Due to the fact that not all races gain stats this way, there's isn't really any reason not to use the 4 point gaining classes.
Of course, this is me speaking without knowing if races get any other bonus, like abilities, feats, spell-like abilities, or physical characteristics.
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