I keep a spreadsheet literally called "games to play". Ive played about half of these so far, but they all meet your criteria, and all have overall good reviews, here's a selection from it, including my own notes: (pardon the lack of formatting coming from a spreadsheet)

A Hand With Many Fingers - 3 hours - Puzzle - Difficult (use pen and paper for clues) CIA mystery

A Wolf In Autumn - 1 hour - Walking Sim - Girls nightmare

ADR1FT - 6 hours - Puzzle - Space station catastrophe

Anna - Extended Edition - 5 hours - Adventure - Psych horror in sawmill, inventory based puz

Antichamber - 7 hours - Puzzle - MC-Escher-esque open world physics breaking puzzle solving

Aporia: Beyond The Valley - 5 hours - Walking Sim - Walking Sim+ (puzzles), awaken in ancient temple in jungle

Ballads At Midnight - 4 hours - Visual Novel - Story of a bard and a vampire

Beyond: Two Souls - 12 hours - Adventure - Ellen Page / Willem Dafoe,

Blind Spot - 5 hours - Puzzle - Puzzle mystery story

Brothers - A Tale of Two Sons - 3 hours - Walking Sim - Heart-wrenching story told with no words

Brukel - 1 hour - Walking Sim - 92yr old grandma retells memories of WWII

Close To The Sun - 6 hours - Walking Sim - Looks like Bioshock, great atmo

Cloud Climber - 1 hour - Walking Sim

Deliver Us The Moon - 5 hours - Adventure - Sci-fi story on moon, some puzzles, some platforming

Dr. Langeskov, The Tiger, and The Terribly Cursed Emerald A Whirlwind Heist - 1 hour - Walking Sim - Very short, hilarious game from maker of The Stanley Principle

Draugen - 3 hours - Mystery - American searching for missing sister in 1920s Norway

Goetia - 7 hours - Point-And-Click - Puzzles / adventure in abandoned house, text heavy

Gorogoa - 2 hours - Puzzle - Hand Illustrated puzzle game

Heavy Rain - 10 hours - RPG - Crime thriller / mystery, multiple outcomes, some QTEs

I Hope She's OK - 1 hour - Walking Sim - Short mystery at a nordic cabin, told through instagram-like messages

Jessika - 3 hours - FMV - Solve suicide of Jessika

Journey - 5 hours - Walking Sim - Atmospheric exploration

Knee Deep - 4 hours - Puzzle - Mystery in a swampland / theater production

Kona - 8 hours - Adventure - Detective in eerie Canada town

Manifold Garden - 6 hours - Puzzle - M.C. escher landscape build gravity bend puzzles

Murdered: Sould Suspect - 10 hours - RPG - Solve your own murder

Scanner Sombre - 3 hours - Walking Sim - Trippy cave-explore game

SOMA - 10 hours - RPG - Horror adventure

Tacoma - 4 hours - Walking Sim - Sci-fi space station adventure

The Fidelio Incident - 3 hours - Puzzle - Short story, plane crash in N. Ireland

The Forgotten City - 10 hours - RPG - Time loop in ancient Rome

The House of Da Vinci - 7 hours - Puzzle - Similar to "The Room" series

The Painscreek Killings - 10 hours - Walking Sim + - Murder mystery, find clues and keys

The Secrets of Darkwood - 5 hours - Txt RPG - Descendant of Might and Magic series

The Signifier - 9 hours - Adventure - Dark, tech-noir

The Silent Age - 4 hours - Point-and-click - Short, fairly easy puzzles, time travel post-apocalypse

The Turing Test - 6 hours - Puzzle - Portal/Talos wannabe

The Unfinished Swan - 4 hours - Puzzle - Paint / blob game

To The Moon 4 hours - Walking Sim - Doctors help dying patients relive life

Untitled Goose Game - 6 hours - TP-RPG - You are a horrible goose

Valley - 8 hours - Walking Sim - Actually running/jumping sim

Of these, the standouts that I've played so far are "Scanner Sombre" and "Unfinished Swan" for truly unique gameplay. "SOMA" and "Heavy Rain" for best storytelling. "Painscreek Killings" for best mystery (minus one very out of place sequence). "Forgotten City" for the best standalone Skyrim mod turned into a self contained adventure.