All chosen apps should be installed with one apt command

[danboid]

MATE welcome should be adjusted so that it installs all packages chosen in a single apt command. It takes forever to install all of your chosen apps all if you are using ZFS on your root drive because it creates a new snapshot and updates GRUB for every package you choose to install.

[lah7]

The next generation of this software intends to revamp the inner workings of installing software. Currently, it uses the aptdaemon library and not the apt or apt-get command directly. No promises on whether the new library we intend to use (PackageKit) will improve this scenario on ZFS.

In the meantime, if it's too slow, you could extract the information from /snap/ubuntu-mate-welcome/current/usr/share/ubuntu-mate-welcome/js/applications.json (for the snap package) and cobble together a script that adds the PPAs, signing keys and installs the packages in one go.