OPTIONAL aggregation of categories

Maybe there’s a way that there could be an option to aggregate some of the categories with others? I’ve just started, and 3 hrs of my time is uncategorized.

Even if it’s not a feature, maybe have a forum or somewhere that people can add more options for the default category filters, especially for frequently used keywords? I know everything would be different for different users, but at least this gives new people (like me) a starting point rather than starting from scratch.