ArchLinux has a fantastic user forum and wiki and with AUR a big amount of packages. But this is also its weakness imo, that many packages are poorly tested and might fail on you, rendering the system broken. Still, since it has such a big community, you will always find help.
Every once in a while i try out Arch, but keep coming back to my little Debian system. =)
For all my pentesting tools, i am using docker images. So in this regard i am indepedent of the OS.