alternative file manager

Hi,
some of my customers often ask for different features of the file manager, for example:
- the way to rename a file
- chance to duplicate it
- different file listing
- image editor (like it was for Evolution)
and so on.

I'd like to know if there is some way to use a different file manager,
otherwise the actual file manager can be improved some way? Where can I find some documentation about it?

Thanks,
Alessandro