I am not exactly sure what may caused the differences but take a look at these two pre-cal measurements of a D550.
Things I did between these two pre-cal runs: logic borad update, main board update, ADC calibration. (The base WP calibration was already 8x128 as this was a replacement board and the technicians here do nothing after replacing parts...)
And as you can see it from the "final" report, it seems impossible to achieve as good results with the D550 as you got on your D8000.
The "good Samsung color" is only good on the D8000 with the Samsung chipset, not with these MStar boards...
I see you didn't use the report style with the absolute results. I think you should try it.
By the way, these kind of delta H,S,L charts does not work as fluid for these Samsungs as I hoped.
It seems perfect for the Panasonics where you have HSL controls but here it requires some brain-work to think it through what those numbers mean and what controls you have (HSL vs RGB -> for Red, R = luma, G+B moved together = S , the ratio of G-B = H but it gets more complicated with secondary colors...).