Funny you mentioned MGS 5. I absolutely ADORE the heck out of that game. I didn't even care about the plot, I just loved everything about it especially the free roaming thing.
As for FFXV, its different for everybody. I'm the girl that platinum MGS
P and Xenoblade Chronicles and still loved it. I'm also that girl who did play all the GTAs and beaten them lol. FFXV is a no brainer for me in that trend of games I really love. I really enjoy the grind of side quests and doing all the "little" things. I know it can pad the game artificially and can be done lazy like but given with how large the world is, I like to absorb much as possible and appreciate what they have worked on it, lazy or not.
Basically most of the video games doesn't offer me enough to fully immerse myself into, and lazy side quests can do just that. I can really just get lost in the world and all the sudden I find myself just enjoying it as it is. I really appreciate being able to play the old classics music too on the portable mp3 player too. <3