Some Key sites for tire research:
Good info on
rolling resistance and puncture resistance:
Tour/E-Bike Tires Rolling Resistance Reviews
40mm gravel tires:
700×40 Tire Roundup | GRAVELBIKE
Best gravel road tires (part 1 and part 2)
Best gravel road tires tested ? part 1 | Road Bike News, Reviews, and Photos
Best gravel road tires tested ? part 2 | Road Bike News, Reviews, and Photos
Schwalbe G1 and X1
https://roubaixcycling.cc/tag/schwalbe/
Review: Schwalbe G-One | road.cc
If you can fit the Schwalbe G-One tyres in your frame, you should get some. As genuine all-rounders they're impossible to beat right now: fast rolling on tarmac and properly capable off-road. They're really, really good.
Maxxis Rambler:
Maxxis Rambler Tire Review | Gravel Cyclist: The Gravel Cycling Experience
The Maxxis Rambler is my 40mm gravel tire (tyre) of choice. They are tubeless ready – yes, real tubeless! – no messing around, easy to mount, roll fast and corner with confidence.
Review: Maxxis Rambler 700 x 40c Gravel Tire - Light and Fast
Maxxis calls the Rambler’s tread a “gravel-specific tread pattern,” and so far, we’re liking it on gravel and dirt roads, trails and grass. Don’t be surprised if you see one of us also racing them when it’s dry this cyclocross season.