I suspect that the forum software changed my answer, which was this -
The latter.
bootstrap a basic system, and install packages on it, as you have seen.
make a usable system, providing (most of) expected programs
Follow the culture of the distro, while attempting to make templates
cohere.
The core team - although reasoned arguments for inclusion/changes are
welcome.
a. Yes
b. Some people decrement, others increment from micro base. You should
also look at use of microkernels.
c. Headless qubes providing single service - e.g. firewall, Tor, VPN.
Micro qubes providing minimal GUI services.