D&D 5E Dungeon room description

[Lanefan]

Agreed. I would likely only do "all rolls" if it were intended for me alone. Though, to be fair, advantage is only ever applied to attacks, saves, and ability checks. But your core point stands. Taken too far can harm clarity or end up omitting valuable details. It's a difficult skill to develop, and easy to mess up, but excellent to have when done well.

Ayup.

One thing I'm still trying to determine is when it's worth adding details as to the materials of the room. The Hole in the Oak regular often has details as to what the floor, walls, and ceiling are made up, sometimes with details, and I admit that it can really help me visualize a room prior to description. But is it worth it? I lean toward no, unless it's a feature that stands out.

A generic "all walls floors and ceilings are dull gray fitted stone with sometimes-crumbly mortar between, unless noted otherwise" at the start of the level or chapter covers this off. Then one only has to note the materials and-or colours if they vary from this.

Another aspect that the given example doesn't have to deal with is how to describe the exits of a room so that they telegraph something about why you'd choose to go that way.

Easy. A room with multiple exits therefore also has multiple entrances, and you often never know which one the party's going to come in. If you get in the habit of always describing exits clockwise (or counterclockwise, as long as you're consistent) going around the room from wherever the party comes in*, and even point out to the players now and then that this is how you're doing it, they won't be as easily able to get a read on you.

* - example: a room with exits in each of four walls - if you go clockwise and they come in from the north you describe in order the east, south and west exits; if they come in from the west you describe in order the north, east and south exits, etc.

Writing it up is tricky. For the four-exit room above I might just say "arches exit east and west, wooden doors lead north and south; each exit is at the centre of its wall", and so what if you end up describing as an exit the entrance they just came in.