"Dr Ego and the egg of Man-Toomba" by Special Agent. Based on the irregularly capitalized title and pseudonymous author, I wasn't expecting much. Yet even in the opening scene my expectations were improved. The PC is an explorer searching the jungles of Papua New Guinea for the fabled MacGuffin "Egg of Man-Toomba". The player can skip the first scene (a trip up-river) by typing "wait". Yet I found so much detail implemented in the tiny canoe and the player's possessions that the boat ride was over before I had run out of things to do. The game calls to mind the characters and setting of "Indiana Jones". Indeed, the final puzzle (replacing a treasure with another of the same weight) is directly borrowed from the opening scene of the first film.
The world modelling is deep enough that a player can immerse themselves in examining details, even while they may be temporarily stalled on a puzzle. I was able to solve all the puzzles without hints (except for one, where I overlooked an obvious side exit) and finished the game in just under two hours. I reached a "win" state with only six of nine points, suggesting there may be a few optional puzzles I missed.
If there is one point where this above average entry might elevate itself to the top of the competition, it would be with better characterization of the PC. I tried to play as a callous European colonialist but wasn't getting enough feedback to suggest this was the characterization intended. Who, then, is this PC? A sensitive ethnobotanist? An academic wonk? An agent of greedy foreign collectors? But this is a minor critique.
My favorite puzzle involved trading goods for services with a native wood carver.