There was a question recently about the different behaviour between statistics=(all) and statistics=(fast) configs where we weren't certain about the exact relationship between fast and all, and whether we could simplify this api by removing or renaming some of the aliases.

This ticket is a timeboxed review of the statistics API to determine:

• Whether the all config is equivalent to fast + cache_walk + tree_walk or if there are additional statistics/features enabled by the flag
• Whether we make the interface clearer to work with by renaming config items (for example renaming fast to basic) or if we can remove some config items

Based on the results we'll either update comments and documentation, or make the recommended code changes.