I had no idea this was a rare color. I bought the bass in Dallas, Texas, sometime in the late eighties. I had been invited to the American wedding of a German friend/ex-band mate (who had gone to law school there and met his American wife) and at the spur of a moment we decided on an inpromptu gig at the wedding since the former drummer and lead guitarist were there as well. We had no gear, so we just went out and bought guitars and a bass, renting drums and backline. The shop only had a couple of basses and this was the only one that "spoke" with me. I remember another, then modern day Fender P in black, but it didn't sound anything like the fiesta red one (which was also cheaper, probably due to the warped neck, which I didn't then notice, or the fact that it had been standing around for ages), even though both my band mates ("that is a weird pussy color, get the black one") and the shop salesman tried to talk me into the black one. Even in later years when I would play it, people would say: "That Fender sounds real nice, but the color is an acquired taste." I used to refer to it as my "Beach Boys bass". It was only comparatively recently that I saw color pictures (as opposed to black and white) of the first Deep Purple line up with Nick Simper on bass and realized that he had played a fiesta red one too in 1968/69. As a Deep Purple nerd that was kind of redeeming as is reading this thread now - belated, but sincere and validating appreciation, thanks!
Re the neck: I'm no expert on Fender necks but this one is more wide than thick too and as regards stability my luthier favors thick over wide necks both with guitars and basses. I don't really care too much either way as regards playability, but prefer the feel of a more rounded neck. But the "warpability" of this particular one is probably more accounted for by how that particular piece of maple grew.
And when I bought it in the late eighties, wide, but "flat" necks were all the rage I thought.