Reply To List is a feature that Evolution has. It would be nice to have an icon so that this can be a clickable feature in the toolbar (something named maybe mail-reply-list). Especially for windows users, what is not click-able is hardly existing. It would be nice if the icon could follow Tango scheme and be nicely in line with Reply To Sender and Reply To All icons.
Finalized version submitted
That's my suggestion for reply-to-list icon. There is also .svg file under attachments.