Schmara, something else to think about ... I write pbs with fairly minimal text, too, and have had a couple knocked back by my publisher in the last year. The reason they've given is that because my work is so illustration-dependent, it's a huge commitment for an illustrator, and for the publisher to feel comfortable asking that of them, they want to feel that there's a reasonable chance of the book selling big numbers, having a more than 'average' level of success.
I found this really interesting, and it does make sense to me. I did have a contracted illustrator sit on my first pb for a year before withdrawing on the basis it was too much work and not cost-effective for him in terms of making a living. So I guess it is a real concern and perhaps something worth thinking about.
Re illustration notes, I always include these, but they're quite minimal - only where absolutely needed to make sense of the text. My publisher is well-known for disliking illustration notes and stripping them from submissions before sending work to illustrators, but she does leave in those that are essential to understanding.