I would like to suggest the implementation of per-query settings. First of all, I refuse to support binary settings serialization because it is deprecated since server version 19.18. The implementation is based on the following ideas

1. Use compiled checked settings names and values (especially for enums). It will protect from mistyping.
2. Easy synchronization settings list with server source code. That's why settings, menus, and defaults are just copy-pasted from server sources. All macros have the same syntax.
3. Settings have to be sent only if they have been set. No data is transmitted by default.
4. Object QuerrySettings is light and easy to reuse in different queries. It contains unordered_map of string views of static names. So it allocate memory only for values.