Need Save As Draft

First of all thanks for the most amazing plugin

I want the following functionality :
o Open a window which will look like outlook.
o The user will enter the subject of his message
o He will also have a space to draft his message (like an email)
o He will also have the functionality to attach documents
o He will also have the possibility to enter his tel # /email id
o Before clicking on send, the system will have a security check.

Some functions met to my requirements but some are not could you pls guide me is there any possibility for save as draft and pre-refilled functionality can be integrate with your plugin