So, some basic questions for feedback and assessment:
- Do you play the lighting rules as presented so that most outside at night is indeed blinded fully obscured visibility?
- To what extent do you mitigate the lighting rules with handwaves, easy access to DV items, or just pretty much ignoring it after maybe some initial setup?
- Do you find frequent scenes where the 5e raw visual blindness fun to play through?
- Do you find it very frequent that after even a short period of play (or chargen) all the PCs have DV-type vision because they just do not want the hassle? if so, did the characters with DV racial features get an extra added something or did they just see their racial feature handed out or hand waved?
-Have you implemented a house rule that changes the lighting stuff (or even if not a rule script around them)?
I place Vision firmly in the same camp as Languages, Encumbrance, Food & Water Rationing, Spell Components, Weather, Open Hands and Item Switching, and all other rules tied to possible challenges during the Exploration pillar. Were I to play a campaign wherein that sort of micro-level detail of resourcing was a part of the style of play of the game, then I would definitely use them. But then again... were that the case, I'd also make up more detailed, granular and specific house rules to that "mini-game" of resource tracking.
There are a lot of rules that are in the game simply for legacy reasons, or so that there is a basic baseline for each and every DM of every style and experience level to use and/or ignore by their choice. They are basic precisely so that those that want to handwave them can, and those that want more detail can layer additional rules upon them.
But just like the Stealth rules, the designers KNEW that every single DM was going to run each and every one of these things in their own preferred way anyway and there was going to be no consensus on how they should work. So there was no point in going too far into the weeds designing intricate systems that 95% of the playerbase was going to ignore or change anyway.