Thanks for posting this! I finally got around to installing it properly (as opposed to appending the commands to my autoexec) and the vpks + module system works really smoothly.
One piece of feedback that I have is that the list of VPKs is super intimidating to a newcomer, and I had to have a couple folks on my stream walk me through selecting the right one. Once I had the right one selected, I couldn't quickly figure out how to install it. I know you have instructions posted with a header that says "Download and Install", but it'd be great if you called out explicitly that the VPKs literally run themselves and that you don't have to add anything do your autoexec to make it work.
In conjunction with my first piece of feedback, it wasn't easy to tell that the VPKs were working. When I removed my custom.cfg, I'd see the mastercomfig echo in console on game start. When I added my custom.cfg back to my /tf/custom/slincustomstuff/cfg folder, the mastercomfig echo would disappear (and I checked my autoexec for a "clear" command). I'm still not even sure if the mastercomfig echo is supposed to disappear when I add a custom.cfg -- it'd be great if I saw the echo whether I ran a custom.cfg or not, and since I know you're reading the thread it'd be great if I got your confirmation here as well!
Again I know how much work went into making this as easy and seamless as possible, and it works swimmingly. Thanks again for doing this!