The Wikipedia link above notes that the first Sevilles were based on the nearly-unique (to them) General Motors K platform.
My take is that first-generation Sevilles didn't look especially luxurious and expensive. Nor did they have what might be called strong "character" -- admittedly a fuzzy, subjective assessment. There was nothing technically wrong with the styling, but the likely intent of the designers was to produce a dignified image and this resulted in something bland, rather than distinctive.
My previous post about Sevilles dealt with the later, definitely distinctive "Razor Edge" version styled under Bill Mitchell's guidance.