If you want to write a concept picture book that editors would want to publish, you should consider:
How many pages is it?
Most picture books are 32 pages. It has to do with way the book gets printed, and other stuff, but really all you need to know is that you have 28 pages to put your story into. (This graphic comes from Tara Lazar.)
Since there are 26 letters, that means mathematically each letter gets one page, with a few pages left over.
Like so (Template from Debbie Ridpath Ohi):
Often some letters get doubled up on pages to create more room for the more popular letters to take up more pages, but that’s not the case with Creature ABC. With each letter getting a full 4 pages (2 spreads) plus a glossary in the back matter, this book has more than 100 pages! That’s almost the size of a chapter book, but without the words. (Can a chapter book be wordless? Hmm, another tangent for later maybe…)
Anyway, I think I’ve made my point here, so how about reading THE GREAT ALPHABET DISASTER?