The thing about Cadillac in the Forties and Fifties was that they always seemed to be putting on the Ritz, not only with their cars but with their ads. Jewelry was what they were about. Feminine. They appealed to women for sure, but also to men, who believed they were buying a high priced... well... you know what I mean, or at least more jewelry for their wife or significant other. Packard in the Thirties was more of the tailored men's suit, with never a wrinkle or limp cravat.
With the Clipper, Packard abandoned this look in favor of a streamlined theme that was neither male nor female, not animate at all in fact, and hard to sell to people with money. They might have done themselves a big favor by putting the '40-42 vertical grill on the Clipper and I think it needed even more. Was studying the cars carefully at Rochester Park the other week, concluded that the hood was long enough but the front wheels were too close to the firewall, perhaps by 8-10 inchesm, and the front fender tops were too flat. Packard lost their lead in part because they lost "the look" and the elegant proportions.
Had they kept these I think they could have done OK for themselves with the powertrains they had, at least to 1951. From that point forward they might have continued with the old Eights but at some loss of sales. By 1955 they absolutely needed the V8. I do think the Ultramatic was a necessity though I understand the argument against it. To buy anything from GM might have reflected poorly on Packard. They needed to show that they could make the big things on their own, that's one of the reasons people bought them.
Agreed Tim, the interiors were sub-par on some models. Looking through the Cadillac brochures well into the Sixties they continued to offer broadcloth in the Sixty Special. Consistency and tradition with never a shortcut or substitute. Am a fan of the '57 Cadillacs in particular, a nice combo of old styling melded to new lower proportions. The '58, '60, '62 and '63/64 are also noteworthy.
As to whether seeing a Packard with 5 MPH bumpers in the Seventies would have been worth it... yes, I think it would have if done right. The '75 Cordoba is a nice design, for example. The projecting bumpers were a step backward for sure, but then again all bumpers projected out in the Thirties and Forties and nobody ever held this against them.