I have been wondering why we can not have a simple option that says "resolve names remotely or proxy-side" instead of local Mapping. That way, you can select either resolving names locally using your DoH exclusively or resolving names using the DNS server of the Upstream IP PROXY address exclusively.
The word "exclusive" is very important in this context and it means that no other DNS server is allowed to resolve names except the option selected by user.
Local Mapping is not elegant enough as many websites has several unknown third party websites that are resolved when you open the intended website. Do you now begin to monitor such hidden URLs and keep mapping locally each time you open the desired Websites? e.g. Content Delivery Networks (CDNs) like facebook, google analytics, twitter syndication, e.t.c.
In addition, can we have supports for customized name resolution for domains on specific ports/ process-names in [Host] field?