All eyes are created different.
Also you Samsung sets and saves the PQ settings such as color etc. separatly for each interface since the PQ charasterices vary by souce. For the settings for DVD player over HDMI can be different for your cable STB using another HDMI connection,
You and family you should try watching material from each different souce and chage the settings to what you decide you like best for both daytime and nightime use if your room lighting is very differet based on time of day
One thing to know is that the default fatory settings such as brightness are set to make the units look the best on a showroom floor with bright lights so as a minimum user normally turn to the brightness settings.
Back in the days of CRT TVs only experienced techs normally were good at "calibrating" the convergence settimgs, However since fixed pixel digital technology TVs do not have convergence settings the use of outside calibration assistance using someone else's eye is normally not required.
Hopefully others reading your post that have you TV model will offer some more specific ideas.