It's kinda fluffy. Most of the advice is good, but basic.
One peeve I have is that it's pushing a firewall solution on the local box. In general, that's best done off-host. Even better are MAC security solutions like AppArmor, which is really easy to set up (frankly much more so than a non-trivial set of firewall rules) and much more capable in general. Typical applications need access to only a handful of paths and capabilities that are well-defined in the documentation.
One peeve I have is that it's pushing a firewall solution on the local box. In general, that's best done off-host. Even better are MAC security solutions like AppArmor, which is really easy to set up (frankly much more so than a non-trivial set of firewall rules) and much more capable in general. Typical applications need access to only a handful of paths and capabilities that are well-defined in the documentation.