Interesting thoughts, Marfig!
I personally agree that we have been patching the old tech for far too long. IPv4 and SSL are perfect examples.
But what amazes me is how WELL some of the old security protocols still hold up, like SSH and Kerberos. The majority of security holes are created by people assuming that things set up in a default install ARE secure...and not knowing differently to fix it.
I really can't believe I'm saying this, but one of the BEST things a small office can do is to buy Microsoft Small Business Server, and initialize ActiveDirectory. There will be a write-up of AD coming soon, but it's one of the most powerful tools you can use to control your network.