You may try installing "gpointing-device-settings" which is a GUI tool for extended mouse/touchpad settings -
It does not create a launcher icon in Unity, so you may have to run it from terminal (or Alt-F2) > "gpointing-device-settings" command.
sudo apt-get install gpointing-device-settings
See if it can set the touchpad to your liking (make a note of the default values before changing them, since it does not have a "Defaults" button). It should be able to save the settings once set. If not, you may have to look into scripting solutions with "xinput" commands.