Re- the Emacs config suddenly breaking... I do something getting more and more common: I put my entire Emacs config in Git. It's a bit more work when upgrading packages (because you have to commit them too) but then there's hardly ever any breakage that's not one Git checkout away (I'd say anyway that Emacs doesn't that often break at all: it's more the usual package dependencies SNAFU of our trade that bites Emacs users once in a while when they upgrade this or that package).
On a funny side note I had a very bad Emacs breakage recently and at first couldn't understand why checking out the latest known correct Git version wasn't working on my main machine. It was working on another computer (btw copying my entire Emacs config is, well, also one git command away, so is backuping). Turns out: for whatever reason the file containing the list of files recently opened by Emacs got corrupted in a very strange way and that's one of the rare Emacs file I'm not committing into Git. Took me a few minutes to sort out.
I do the same with my .vim folder. You can place your .vimrc file in there as .vim/vimrc and now everything is backed up in git. I've been working this way for a few years now and can get setup on a new machine in a matter of minutes.
On a funny side note I had a very bad Emacs breakage recently and at first couldn't understand why checking out the latest known correct Git version wasn't working on my main machine. It was working on another computer (btw copying my entire Emacs config is, well, also one git command away, so is backuping). Turns out: for whatever reason the file containing the list of files recently opened by Emacs got corrupted in a very strange way and that's one of the rare Emacs file I'm not committing into Git. Took me a few minutes to sort out.