There's a lot of factors here; were you on dev or master? What I suggest doing is using dev, but pinning yourself to a particular commit. Once you see that things are working, using that commit across all your machines. You can have a fork that you never push to, except to fast forward when you feel like upgrading. Just pull from that fork on new machines instead of from the main repo.

The only other thing that can break you other than updating spacemacs is updating packages, but that's a factor with vanilla emacs and with vim. This happens occasionally but not too often.

Also keep in mind: spacemacs is not all or nothing. There are many, many layers that are higher in the dependency tree, that both get less attention and are easier to swap. For instance, even though I mostly develop in C++, I don't use the C/C++ layer from spacemacs. There were things I wanted that were missing (like rtags), and things that I didn't want that were there (like older tags solutions).

I started out by just configuring rtags inside a single simple file, the same way a vanilla emacs user would, and I dropped the C++ layer. I eventually added more stuff and wrote my own C++ layer. I'm quite happy with the result. I still got a ton of useful layers/packages from spacemacs that were easily setup and configured, like evil, magit, helm, company, flycheck, etc. And the whole layer system itself made even the parts that I customized myself more modular.