Given that I've never owned a 650b bike, (although that will hopefully change,) take this with seasoning to taste, but:

If you just need a bit more traction on fire roads, the Continental Contact Speed look like they might do ya. For more dirt capability, the Gravel King SKs might be good. A little more than that, and something like the Terravail Ehlines starts looking pretty good. Beyond that, you're into hard-pack MTB territory, and I don't know what's current in that space... it's been 10 years since I did any mountain biking, and those bikes were all 26".

I've ridden all three, but that was only test rides when I visited Rivendell, so all I can really comment on is the noise factor. All were noisier than a road slick or file-tread tire. None was very objectionable, although if I were spending significant time on pavement, I probably wouldn't pick the Ehline. Maybe it was the Clem Smith Jr. that it was mounted on, but the combo seemed slow. Not a total dog like a full knobby on asphalt, but slow enough to notice. The Conti had a sort of high-frequency "hum" when coasting. I kinda liked it, but I can see where someone might find it irritating. The SK made a bit more noise than the Conti, as you'd expect from looking at it, but less than the Terravail, (let alone a full knobby,) as you'd also expect from looking at it.

Bear in mind that this reflects about 10 minutes on each tire, all on beat-up pavement, and on upright, step-through bikes with baskets and all the farkles. You know... Rivendells.

For reviews, I'd be looking more at gravel & bikepacking sites than road or MTB ones. The Continentals don't seem to get much attention anywhere, but maybe I'm not looking hard enough.

Also, please to post pictures of le vélo?

--Shannon