Hello,
I’ve been using kicksecure-based templates for a while now without many issues. It’s true they’re a bit heavier and use a bit more resources (I’ve had to up the max ram of sys qubes of ~150/200Mb), but it’s a trade-off you may or may not want for extra security.
I did some testing and you can install security packages without full distro morphing:
Did you use the --no-install-recommends parameter when installing packages?
The link is missing, but I haven’t had this problem.