I agree with M C. The style for the story isn't going to be the make-or-break for the artwork. You should experiment and thumbnail different styles and see what works for you and the piece. You can still make something amazing using an unconventional style for the story. I'd say, focus more on what parts of the story you want to bring to life.

I think the style is yours to choose! use what you feel is right, express yourself through that choice, and also you can play with the viewer's mind: do we expect a children book illustration? then shock us with a gritty futuristic one, that sort of thing, hope this helps looking forward to seeing what you decide to do