Support for stats.json in monobundle is now available in Fusion 2.7. This provides the capability to audit the monobundle and discover potential performance optimizations.
There are webpack stats audit tools available as npm modules. Example: https://github.com/chrisbateman/webpack-visualizer
If one of these modules were included as a dev dependency in a Fusion Features project, bundle audit reporting could be made on-demand as an npm script.
This sounds like an interesting idea that we will look into when we make further improvements to the Fusion CLI. Thanks!