I just want to suggest something simple.

Is not more reasonable that if reach the limit of the Quality point, the percentage of my final item ends in a HQ?

Just think about it. I don't see any sense that if I have 800-1000 points i just still have 50% in HQ if I reach the max points. If I just try to get 1000 points I'm risking my recipe and all that for nothing? Because to have the same % to 800 and 1000 Is just not fair and reasonable.