Games like Better World
Games like Better World include Firewatch, What Remains of Edith Finch, Layers of Fear (2016), Mouthwashing, and The Beginner's Guide. We matched them by the tags players give Better World on Steam (Adventure, Indie, Walking Simulator, First-Person, and 1990's): closest matches first, and among equally close ones the better-known games.

Firewatch
Shared: Adventure · Walking Simulator · Atmospheric

What Remains of Edith Finch
Shared: Walking Simulator · Atmospheric · Adventure

Layers of Fear (2016)
Shared: Walking Simulator · First-Person · Atmospheric

Mouthwashing
Shared: Indie · Atmospheric · Walking Simulator

The Beginner's Guide
Shared: Indie · Walking Simulator · First-Person

Blair Witch
Shared: Adventure · Indie · First-Person

Fears to Fathom - Woodbury Getaway
Shared: Adventure · First-Person · Walking Simulator

Outlast
Shared: First-Person · Atmospheric · Horror

No, I'm not a Human
Shared: Indie · Horror · Atmospheric

Poppy Playtime
Shared: First-Person · Horror · Indie

Amnesia: A Machine For Pigs
Shared: Walking Simulator · First-Person · Atmospheric

Sally Face - Episode One
Shared: Indie · Adventure · Dark

Amanda the Adventurer
Shared: First-Person · 1990's · Adventure

The Stanley Parable
Shared: Indie · Walking Simulator · First-Person

Road 96
Shared: First-Person · Adventure · 1990's

Among the Sleep - Enhanced Edition
Shared: Indie · Adventure · First-Person

No one lives under the lighthouse Director's cut
Shared: Indie · Adventure · Atmospheric

Gone Home
Shared: Walking Simulator · Indie · First-Person

Little Nightmares
Shared: Adventure · Atmospheric · Indie

Still Wakes the Deep
Shared: First-Person · Walking Simulator · Adventure

Slender: The Arrival
Shared: Indie · First-Person · Horror

SOMA
Shared: Atmospheric · Horror · Dark

Visage
Shared: First-Person · Adventure · Dark

From The Darkness
Shared: Indie · First-Person · Walking Simulator