Beyond Aion have its own GP loss system, so the GP deduction bar is just visual. I think that the Deduction bar couldnt get changed that easily, thats the reason why the normal GP deduction of the Official Servers get appropriated.

Correct, the values on the Abyss ranking table are unfortunately nothing we can control. The client has some default values which we cannot override.
But on each login you get a system message which will show you the (real) current loss for your rank.