Like...certain characters had special speech bubbles/text that gave you a vibe for their voice in a visual medium.

And like, that Sturridge fella? He fucking nailed it. I heard him speak as Dream and went "! Ok, that's perfect, I now cannot imagine this working with any other voice."

And Del's voice is....difficult. Even when I cosplayed as her I couldn't do any in character speaking except for "I am following my fishie."

Examples coming up of Delirium's speech

One with Del and Dream

Now, Deliriun is a bit...chaotic. Oscillates between child-like and adult, airy and stern, bit of a twisted sense of humor. She may be naive to many things but she's not dumb. She is, in fact, quite clever when she needs to be.

Delirium used to be Delight. Since her transition began, her hair changes frequently in both length and color (most cosplayers just go with a rainbow wig for simplicity), and she has 2 different colored eyes.

And that change will show in her speech bubbles - from what I recall the words become a bit more uniform in size and her eyes appear to be one color (blue, I think?). She cannot do this often, though. It takes effort and it hurts.

Nothing But Spoilers Here

I know I have to wait a good long time to find out, but I'm trying to imagine what Del's voice might be like in those various circumstances and it's hard to conceive.

I did see someone on tumblr suggest Sadie Sink for Delirium and that could be interesting. Not sure if that would really work out with Stranger Things' shooting schedule though.

Upon further reflection i'm sure I have something about Del's eyes wrong. I gotta pull out Brief Lives and correct myself

VINDICATION

Aha, I also discovered why I thought I was wrong.

Brief Lives is my favorite arc of Sandman, and it's volume 7 of the (10) trade paperbacks. I read it many, many times and apparently I have Del burned into my subconscious still

I must have been remembering (faintly) this panel