A cookbook can be unpractical, bulky and might just end up on a bookshelf somewhere. Recipe cards is the lightweight and flexible version of a cookbook. Use them, put your favorite ones on your fridge and when you’re done with them, give them to a friend.
Displaying food is not usually done with illustrations, but why not? By showing an illustration instead of a photography, apart from the visual experience, leaves the cook with less expectations of the end product. An illustration is much less detailed than a photography and makes more room for creativity and playfulness.