My idea is to create a mod that will improve the book and quill, because for now the only thing you can do is write. If you want to go back you must delete, you can not re-edit what you accidentally signed. My idea is a GUI where you can edit a signed book if you signed it, paint words in the text, go back to the previous sentence without delete text and write a description for the book. Please notice that all of those things are possible with commands. Of course anyone who wants to do this mod can add any ideas he wants, from cover colors until text in different size (actually, those ideas are bad because then you can't use the book without the mod. that's why I only want tweaks that possible with commands). Thanks for reading!