Bootstrap is a small footprint though, e.g. typography module is 2.8kb gzipped. Add modules as needed, they're all well designed/thought-out. Shrug.

Indeed, with Sass, just comment out what you don't need. I rarely use much beyond the grid and normalization, it nice as its a predictable setup that you can plug in front end devs, and almost everyone knows the media queries vars (if they don't, they can google them) and such.