I'm not getting flamed and I think you're quite right in what you say
I already built my own linux kernels on gentoo and at some point I was writing some easy kernel modules, done some unix programming with threads/semaphores/dbus interaction.
Kernighan & Richtie's book is the first on I read in fact.
I came across some good sites in the past few days, mainly corelan.be, krebsonsecurity and pentesteracademy (I follow the plan of their course but learn from different websites) and I now realise mass exploitation of servers can't be done anymore. Or will at least be different than what I'd have thought.
It used to be a time where you could just google d0rk and easily find targets to root or hundreds of easy SQL injections to upload your shell but those times are over as it seems.
For the moment I'm reading
[size=78%]https://docs.google.com/file/d/0B-F3NpsEIXCYcDZaUXhfdXlFM1k/edit[/size] "Python - A cookbook for pentesters, hackers and forensic analysts" which is quite good.
I also know that I'll _for sure_ need to learn assembly but I really can't be arsed at the moment I'll just begin with simpler / high level things such as SQLi injection, Javascript, Python, using Nmap / Metasploit correctly and stuff.