I would always prefer SM’s long text plus artwork format. It strikes a perfect balance for me. Pure text can be extremely hot and immersive, but I often wish for clear visual depictions of the characters and of what is happening. Conversely, when I read comics I sometimes wish there was more text, more detailed descriptions of the sex, the emotions, and induction.
Text with portraits feels kinda weird cause even during intense moments, the characters just keep staring straight into your soul.
If images genuinely elevate the text, and you have the artists and/or the tools, I don’t see why one would choose the other approaches. A practical compromise is also available: release the full text first, then later add the artwork.
I agree with all of this. I'll add that the unity of image style and coherence is a big part of why SM works, for me. There's exactly two images (two of the dream cards, Allison and Annie embracing and Allison as prostitute) that don't quite match the style of everything else and it annoys me whenever I see them. I could see the text without images, or with placeholders, released as a sort of pre-release, early-access thing, but I would want there to be, eventually, final art.