One of my biggest gripes right now is the mapping of lifts / elevators because there is no good practice to mapping at least with buildings of outdoor lifts.
The most simple is a highway=elevator as a node but this also means you can’t really use an area if you want to. If you do draw it as an area, you can have the elevator as part of the node or as a separate thing which both have their own side effects.
For example, if you only connect the outdoor part of elevators, this breaks routing but if you draw a way inside the building, it’ll look rather ugly. (Indoor mapping is overall spared at least if you don’t draw ways in addition to indoor=area/corridor)
Some mappers even ended up misusing layer=* because they didn’t want to connect the ways with the buildings and add doors, in turn placing the building or way above or below the building which adds to the problem (I’ve noticed this on some station lifts in my region).