Here's how I do it. First, I set up a user to have the desktop look and feel that I want.
Then I make a temple for all new users to have that desktop when they are created ...
Note: Remove any parts that you don't want new users to have in common, like thunderbird.
Code:
rm -rf /etc/skel
mkdir /etc/skel
rsync -av --exclude='.thunderbird' /home/fred/ /etc/skel
or
rm -rf /etc/skel
mkdir /etc/skel
cp -R /home/fred/\. /etc/skel
rm -rf /etc/skel/.thunderbird
When the new user first logs in , there may be a message about running as the other user. It also says that if you click on ignore that won't be an issue anymore. So, click on ignore and the message doesn't pop up anymore and the new user now has a desktop just like the first one.