The display panel is what it is - a mediocre TN panel. I'm not calling names, it's just the truth. You can try to improve it by:
- using the calibration tool in Sys Prefs
- if you have an LG display, googling for a tweaked ICC profile for the display
- if you have the hardware, using a colorimeter to generate a profile specifically for your display
There are hardware limits, though. There is nothing you can do to improve the viewing angles, the basic ability of the display to cover a specific color gamut, or the display's resolution.