Yii's by-default directory organization works well enough, but there are several steps one can take that improve the security and serviceability of the system, especially in the context of multiple Yii projects on the same machine (including multiple versions of the same project).
We all know how to upload the content and images at the same time with refreshing the page. And uploading the images using Ajax we have faced some issues, here i have fixed the issues and both content and photos are uploaded using Ajax. And both content and images are stored in the different tables
I've seen many tickets regarding how to show friendly delete confirmation using CGridView's CButtonColumn in ajax request. If you are using relational database, after producing CRUD functionality when you try to delete a record in ajax mode which has child record it can't be deleted and you can see the ajax loader forever. By this way you can't show the users if a record has been successfully deleted or if there are some problem in flash style (setFlash() / getFlash())
With the adoption of PJax on Yii2 things have change quite a bit with GridView when it comes to work with them in AJAX mode. It will probably be confusing at the beginning, but then you will soon realize how powerful the new approach is.