I think most people in the English-speaking world get an idea beaten into them during their education: that you should write in short, to-the-point sentences that have a very regular and clear structure.
But here's the thing, go read any piece of text that you consider lush and evocative, especially in a texty video game context, and just... pay attention to how much punctuation is there, how often there are subclauses or irregular breaks (em dashes, etc), how often there's grammatical oddities like funky tenses. It's usually a lot!
This doesn't just go for your Fallen Londons and Disco Elysii, either. Look at any game that has a lot of short dialogue without VO, like Animal Crossing. You'll see heavy use of ellipsis, big variations in style from different characters, odd or irregular sentence structures. Lots of little ways of building interest and voice. You can do it without walls of text; you can do it at a grade school reading level.
