I've always liked these. Working with limitations always helps push an author creatively, and as a player it appeals to my enjoyment of multiple layers of complexity and being able to feel like my actions are making an impact altering an environment in noticeable ways.

Any thoughts on designing or play experiences with a one room game? (I have mixed feelings on whether the 'travel to different areas of the room' style of design really counts or if it's a bit of a cheat...)

Try Hunt the Wumpus 2.5...
One room, reloaded with new descriptions and exits to looks like several rooms...
"Soon", I will finish V3.0 which will have 30 to 40 room descriptions randomly selected for the 20
rooms of the map.
Except for option "0": No monsters...
Check out the code... if you dare...

FURBY MCQUACK!! Lol

But I think you've played that one! ;)

One word: Locked-Room Mystery. (Okay perhaps two words... Okay, one hyphenated word and one un-hyphenated word!)

Off site link:
https://en.wikipedia.org/wiki/Locked-room_mystery

also, this too (as electronic games or real-life physical-world puzzle rooms you try to escape from):

https://en.wikipedia.org/wiki/Escape_room

https://en.wikipedia.org/wiki/Race_to_Escape

there's a slowly growing number of them in the U.S., one of our previous programming students along with his buddy from IBM, created a physical escape puzzle room, using lots of various physics for the puzzles (such as real lasers, though dispersed so no one gets blinded, pressure plates and etc) in trying to escape from the room. It's not easy for them to get permission from the government to set up such a business/facility, the joys of becoming more and more slaves of plantation government, having to get PERMISSION (free people don't need permission, slaves do) for everything... from our slave master plantation government, sighs.

You could also try searching the IF DataBase for one room games. (or any other type you may want.) They are not necessarily QUEST games although you may be able to set that in the advanced search.