Using multiple AIs to fine-tune details and generate a variety of options can be helpful in identifying the most effective visual solutions. However, this approach risks introducing inconsistencies and mismatches that may undermine overall coherence and readability, potentially causing distraction for the player/reader. If variations in artwork remain subtle, these issues should be manageable.
Although I usually emphasize the importance of writing, including both narration and dialogue, which is often undervalued in the AVN field, it is important to keep in mind that in a visual novel narrative and visual components are closely intertwined. Visuals often serve as the initial point of attraction and can significantly influence whether players stay engaged, often more than the story itself, justifiably or not.
Of course, this is just my personal opinion on the matter.