This is what saved bootstrap as our goto framework in our shop. Every new project starts with most modules commented out and some early attention to setting the global variables and using the mixing. This keeps things small while new modules are a simple uncomment away.
Yep, exactly what I do, +1 for using bootstrap's variables as much as possible too, I don't think a lot of people realise how powerful bootstrap's variables are, and can greatly cut down the amount of CSS you write.
Edit: examples
https://github.com/greenriver/boston-cas/blob/master/app/ass...
https://github.com/greenriver/boston-cas/blob/master/app/ass...