I would like to have Sunlight Sensitivity implemented ...
Would be kinda frustrating tho, many people are allready complaining that they dont hit as often as they want to ... also feel free to corect me, but this would mean no Sneak Attack for Drow Rogues on surface?
To give a flavour of this without it being really frustrating (or needing a day/night cycle), it could be that drow only get disadvantage when standing in full sunlight out of doors. The game is already calculating the amount of light for stealth checks. It might be thrown by, e.g. torches and fires outside in daylight, but I don’t think that would be too noticeable. I think it would even add to the gameplay experience of a drow, actively looking out for shadows to lurk in. Though the game would need to give you better visual cues about what spots were shadowy without going into stealth, that would be desirable anyway.
EDIT 12/08: Well, after playing this game more hours than I care to admit, I have just realised that it's possible to press <left shift> and hover the mouse over an area to find out whether it's in full light, partial light or shadow, as well as to see vision cones while not in stealth, so the game is already doing more than I thought it was
By the way, is there a 5e spell that would counteract the disadvantage? Darkness affects darkvision doesn’t it, so unless you’re a drow warlock with Devil’s Sight that’s not going to help you.