Apart from wanting the GP winner to be the top scorer, which I don't agree with, but understand why people want that. There are many issues with the current scoring system.
If 5 riders are tied on 6 points, why do you need to split them via countback?
If someone scores a 15 point max but has an ef in the semi, do they really only deserve 9 points?
The other issue is after semi 1, you don't know if the 3rd finisher is 5th or 6th, or if the 4th finisher is 7th or 8th. The world title / rostrum position / top 6 qualifiers could end up being decided by the meeting wildcard!
There are far simpler ways to ensure the GP winner ends up with the most points, if that has to be done.