Option to show the dock with a double mouse click over an empty area of the panel and also the option to set a shortcut key for this (example: Meta + Space), available when auto hide is enabled.
no idea what you mean with "Option to show the dock with a double mouse click over an empty area of the panel" . The shortcut to show a hidden dock/panel is Meta+` and you can also change it from plasma systemsettings->Global Shortcuts->Latte Dock
already supported...