Non-critical packages (Desktop/Plasma group, Utilities) went through try_install which installed them one-at-a-time (45 individual pacman calls). Override operation_try_install in PMPacman to batch all plain-string packages into a single call, matching the behavior of operation_install.
Also:
- Remove antergos-plasma-theme from rootfs (profile.yaml) and both netinstall Plasma groups
- Add allowFileSystemTypeSelection: true to both antergos and minimal partition.conf
- Both main.py files (profile + minimal) get the batching fix