All images that Canonical provide are server images which do not include a graphical environment. You can create a custom Ubuntu image however I would suggest using cloud-init user_data to perform a desktop install. This will allow you to install the latest supported Ubuntu image without having to maintain a separate image. On first boot when cloud-init runs it will install the ubuntu-desktop, kubuntu-desktop, lubuntu-desktop, or xubuntu-desktop metadata package which should pull in all desktop packages.
#cloud-config
packages:
- ubuntu-desktop