The 800 lines are you or your team's own fault; it's just a file run in NodeJS, it's trivial to separate it in task-specific files and load them with either `require` or one of the `loader` projects. Build tooling (what Grunt is) configuration, maintenance and maintainability is also the responsibility of developers.

Of course, the async thing (and such) is something I agree with, newer tooling has iterated and improved on Grunt.