I use webcomponents (specifically Polymer stuff), and all I do is just roll together all the components I'm going to need for an app in one big concat-and-minif

I use webcomponents (specifically Polymer stuff), and all I do is just roll together all the components I'm going to need for an app in one big concat-and-minified file. You don't have to fetch a gazillion components, any more than you have to fetch a gazillion .js files - cat, minify, gzip works on webcomponents as well. Plus, as other people mentioned, http2 solves this problem as well.