I just did some measurements and am impressed on both fronts: DNS recursive resolution is faster than I anticipated, but also page load times for well optimised sites are also very fast (sub 0.5s). Here's some data:

Recursively resolve bbc.com: 18ms https://pastebin.com/d94f1Z7P Recursively resolve ethz.ch: 17ms https://pastebin.com/x6jSHgDn Recursively resolve admin.ch: 39ms: https://pastebin.com/DUTg8Rit

Page load in Firefox: bbc.com DOMContentLoaded: ~40ms, page loaded: ~300ms reuters.com DOMContentLoaded: ~200ms, page loaded: ~300ms google.com DOMContentLoaded: ~160ms, page loaded: ~290ms

So it's quite reasonable to do full recursive resolution, and you'll still benefit from caching after the first time it's loaded. One other idea I had but never looked into it was instead of throwing out entries after TTL expiry to just refresh it and keep it cached, no idea if BIND/Unbound can do that but you can probably build something with https://github.com/hickory-dns/hickory-dns to achieve that.