Instant Immersion - Dynamic Ambient Sound
The days of just slapping an ambient sounds track into a level are over. Sure, you can still do it of course, but you will sacrifice immersion in a massive way. And again, to repeat my main theme from the first blog post, people won't understand why the game isn't grasping them. They won't say "This is terrible sound design" because 99% of gamers, listeners, audience, whatever, just don't think cerebrally about sound design.
Just to establish street cred as a dev, I'm making a game currently, Lost and Hound, to show game devs that you don't have to treat accessibility as an afterthought; it's designed for blind gamers to be able to play at the same level of skill and fun as sighted gamers. I approach audio ambience very aggressively; in the first few minutes of gameplay, every tree has a different bird species or call, and that blueprint (yay ue4!) is on a timer that switches to a frog, or cricket or owl at nighttime. That means that no two walks through the forest are the same, because in a 3d space it's near impossible that people will take the exact same route wherever they go.
This is one of the easiest tricks to make your gamer's experience feel dynamic and real - and it adds to replay value. Replay value adds to word of mouth and gamers recommending your game to friends - which is the best form of marketing.
Friends don't let friends use a single track for ambient noise. Don't be that guy.