Did a quickscan of "How to secure your new linux installation". Looks good.
Found some things that could be added though. I disagree the partitioning scheme is a definitive one, this depends on the task the server has to perform (also point out problems with single vs multitask boxen as in basket, eggs). Maybe show more examples (firewall, database server, syslog server)? (Mount flags?) Then the installation process skips to runlevel and detecting open ports. IMHO the next stage (before installation reboot) should be protecting the asset by either making services stop until configured or raising the firewall to only allow your management IP (range).
There's more (restrictions, auditing, backups), maybe I'll add some remakrs later on. Before I forget: you could point out there's more (in depth) docs, have a look at links
here (not meant in an intimidating way, OK).
In any case well done, and I hope you'll expand your docs. Maybe submit them as LQ Answer?