If you enter the following PoSh commands on your Windows Server 2016 TP2 you can install the “full” GUI for this system:

get-windowsimage -imagepath InstDriveLetter:\sources\install.wim
install-windowsfeature server-gui-mgmt-infra,server-gui-shell -source:wim:InstDriveLetter:\sources\install.wim:2

Keep in mind that you have to change InstDriveLetter to your drive which contains the Windows-Install-ISO (or disc)