"Add file" sub-module lack of any important features

Hi.
When you go to "content | content type" (and after creating a custom content type), you will see this "add file" list.

It is just too simple.
When you click on it, you can set the properties of the "add file". However it doesn't have lot sof useful features like:
- file size limit
- file extension limit
- thumbnail (or preview) of the file (if possible)
- (any more to add?)

Thanks!