The PAPI lights are unrealistic small. They are hardly to see during the landing. Furthermore the lights must be white or pure red, but the red lights are orange.
It's possible to adjust the size of these lights. In the flie lights.txt in the folder
X-Plane 11\Resources\bitmaps\world\lites go to the section Sergio’s Real Airport Lights, line
BILLBOARD_SW, VASI. On the right you see 100 -99 0.0 0.0 0.7. Change 0.7 into 2.0.
It would be nice when LR change this values.