Author here -
The purpose of going through and removing the malicious scripts was to learn more about server security. I figured if I had been compromised I might as well learn what was causing it and how to fix it.
I have since toasted the server and set it back up with all of the things I mention in the article. I wrote the piece because I felt that there might be others out there who can learn from my mistakes and to also have a record for myself.
We are always learning and sometimes we need to learn the hard way, I got lucky in that this was on a side project and not any real client work.