Maybe with options like:
- All available
- Per region (as some do not want American DNS servers due to legislation there)
- Custom lists, for the people that want total control over which DNS to use
Also adding your own Encrypted DNS providers would be a nice feature, but I would already be very thankful if these would be added: DNS Privacy Test Servers - DNS Privacy Project - Global Site
A prerequisite of using DNS lists with randomisation is of course a lot more Encrypted DNS providers.