Set Start of Week, 12/24 hour, Celsius/Fahrenheit, etc. Separately

Is your feature request related to a problem? Please describe.
When choosing a locale and/or language, there is no combination that provides me with what I want. Assuming that everyone using a particular locale from a small selection of locales will want the same settings is a major oversight of human behavior.

Describe the solution you'd like
The ability to set the below listed settings separately from locale as desired:

• Start of week
• 12/24 hour
• Temperature unit for weather
• Date-time formats

Describe alternatives you've considered
I looked at forums and the manual expecting that I missed some important detail on where/how to individually change these settings.

Another alternative I have to offer is as follows. Is there a NextCloud app developer (that is skilled and knowledgeable) that wants to earn some money making a weather app that works? The separate weather app on the "app store" is garbage.

The issue does not identify any files, tests, or entry points. Start by locating Nextcloud's locale and user-preference settings, then determine where start-of-week, clock, temperature, and date-time preferences are currently derived; done means each setting can be changed independently of the selected locale.