@AdamJ you're the best. Thank you.
Here's how I'm thinking about this new pair; black, western-style cut. Or at the very least, accommodating to cowboy boots. No denim weight that I'm targeting. Most seem to come in between 13 to 19 oz, but I'm good with any weight. If I were really pressed, I might trend to something lighter since I'm flush with heavyweights, including three pair of IH. And as for weather, I'm in the Pacific Northwest of the USA. It's not unlike much of England.
The options (all pictured) are what I'm working through:
My standard (the standard?) is the Wrangler 13 MWZ. They offer an accommodating top block and look great with boots, hence the Cowboy Cut moniker. The black MWZ 13 is always an option, but it's not selvage.

[Source: wrangler.com]
Wrangler Blue Bell black. Selvage, similar cut to the 13 MWZ, albeit with a much higher price. Bonus is that it comes in a 34 inseam, so no hemming. Oh, and a leather patch!

[Source: wrangler.com]
Freenote Wilkes Western. I had this noted from a while back. Fits the bill, except the leg opening is narrow at ~8". And the pockets are a bit low on the seat.

[Source: Freenote Cloth]
The ol' AI Machine suggested the Fullcount 1101. They look sweet, and I don't yet own a Fullcount. Issue here is that the inseam stops at 32 inches. Very little is left for stacking.

[Source: Blue Owl Workshop]
Brave Star Mojave. This was the original inspiration... and the usual Brave Star caveats apply. I have one pair of Mojaves, but I get some bucketing with my boots due to the tapered knee. And there's always rolling of the dice with the fit and finish here - I ordered a pair of their Desert Bone Mojave, and I swear it was Skinny Straight with Mojave pockets... I have two pair of True Straights that kind of work, but I don't like the 8-inch opening to wear with cowboy boots. Still, the Mojave remains a strong contender.

[Source: Brave Star Selvage]
Iron Heart 634. While currently available in indigo, I don't think black is currently available. Also a strong contender, albeit with a lower rise.

[Source: IH UK]
Others I considered and aren't quite hitting the mark:
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TCB 50s: much bigger thighs
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Sd'A Regular Straight: similar to the TCBs, big thighs
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Sugar Cane 1947 Straight: I already own two Mister Freemdom pairs that are manufactured by Sugar Cane. I also have a pair of Sugar Cane Okinawa fiber blend. So maybe?
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Iron Heart 1955: Close, but the thighs are bigger than I typically pefer and a bit too much taper, with the hem coming in under 8.5 inches
What else should I consider?