On first run (and upgrades) we start extensions to register their background events and such. We do this also for built-in extensions like the settings page and various bits of code that back services like text-to-speech. This code slows down startup considerably on the critical first run, and also since Chrome updates itself a lot, you'll also hit this more often than you may think. On my linux desktop (no corp policy) I saw 13 processes total on first run on a clean profile.

These built-in extensions can be registered without starting processes. 
In browser/extensions/component_extensions_whitelist we have a list of built-in extensions with a locked-down owners list to prevent regressions of extensions.

My idea is to add to this list the permissions and registrations required for each built-in extension statically, and then skip the normal launch-an-extension-process registration for those extensions.

I think it would be beneficial if the permissions and event lists were also in the locked-down directory so we can keep a handle on what types of events teams are listening for that will require extension process launches.