change completion priority

The priority of completion proposals poses a problem:

According to the documentation https://sublime-text-unofficial-documentation.readthedocs.org/en/latest/extensibility/completions.html

Priority of Sources for Completions

 - Snippets

 - API-injected completions

 - .sublime-completions files

 - Words in buffer

I.e. the words in my current buffer are not even shown if there are many .sublime-completions

I would like change the priority, or have different keyboard shortcuts for different kinds of completions