We are fine with your Visual Studio plans. We only use VS2012 at the moment and actually would like to migrate to VS2013.
Not so sure about the use of chocolatey though. Are you planning to use it to download libraries required by the build or for installing software/tools required for the build? Both look a bit problematic to me, because chocolatey (as far as I understand it) always acts globally on the target machine, meaning that it installs the libs/tools/software not locally inside the build directory but globally on the machine. I wouldn't like that at all. I don't want a build tool/process to install anything outside the build directory. If you manage to use chocolatey to only work in the build directory that's fine for me. But I'd strongly vote against any use of chocolatey to install libraries, tools or any software globally or outside the build directory. I wouldn't like a build tool/process/system installing anything on my machine for me automatically. Kind of like calling apt-get on a Linux machine from a build script. I think that is a no-go. Also, chocolatey is not so good detecting installed software that was not installed by chocolatey itself and would often try to re-install software that is already there. I'd vote against using chocolatey in the FreeSWITCH build if you ask me. Wouldn't nuget be the more natural choice anyway to install modules/libraries in Visual Studio? Just my opinion.
Markus