Beastman custom classes - What do more points in Orc get you?

Have decided to firm up my system knowledge, and have been going through the Axioms articles. Axioms 2 gives rules for beastman custom classes. I think I understand the custom classes rules well enough that I should be able to understand the beastman custom class rules, but there's something I don't understand, and I'll use the Orc custom class as an example.

If you get all the Orc custom powers from even just having Orc 0, why would you take more points in Orc? I understand it stacks with points in Fighter, but it appears to cost more than points in Fighter (in terms of XP cost), and extra points in Fighter would get you extra stuff. So what do more points in Orc get you?

Are you adding together the cost for orc values? It’s not additive. Orc 1 costs 250 points more than Orc 0.

250 per additional Orc Value past 0, and it stacks with Fighting for the purpose of calculating attack throws only. Since Fighting costs 500 per point, if all you want is attack throws, increasing Orc value costs half as much as buying it with Fighting.

I have no idea what I was thinking (and suspect I may have fundamentally been misunderstanding something about the process), but your advice causes me to go and check the values again, and I believe I understand them now. Thanks Aryx.