I started this as a reply about the differences between "Richard" and Cooper, but it morphed into a broader topic so here goes:
First, I think "Richard" is sort of a classic "alternate universe" Cooper. You know how "alternate universe" is used colloquially? The way we talk about how someone might have turned out if they'd been born the same person (biologically) but circumstances had been different? I think that's what "Richard" is to Coop.
So let's think about how much is different about this universe compared to our universe. Is the only difference that Laura Palmer didn't die? I'm saying NO, and the big reason is that in this universe, Laura Palmer isn't even Laura Palmer - she's Carrie. Coop isn't Coop and Diane isn't Diane. The differences must be more wide-ranging and earlier in origin than they would be if Laura's murder/not-murder was the only difference.
So... many things are different about this universe. It's like the bargain for saving Laura was that we had to throw out our reality and blindly choose the reality behind Door #2 - take it or leave it. "Richard's" formative experiences have been different from Coop's - perhaps completely different - and that's why he's not the same person.
I don't think Coop was counting on this. He expected ripple effects from Laura not being murdered, but he didn't understand it was a wholesale swap of one reality for another - which is what leaves him so heartbreakingly baffled at the end.
There doesn't have to be a causal relationship between the two places.
In fact, I don't think there is, since Dale and Diane still had to travel to place #2 after Dale intervened with Laura.
The alternate universe had traffic and loud truck/car sounds when Richard/Coop was driving and at Judy's diner. This contrasts with the absence of traffic in the Vegas suburb and a lack of loud truck/car sounds at Norma's diner. The Odessa traffic/loud truck sounds symbolize the harshness of Odessa and the harshness of this alternate timeline. Also, when Richard/Coop was driving, he had to maneuver around other cars and not hit them, contrasting with smooth driving by original Coop in Twin Peaks.
Fire walk with