Toy. An expensive toy, but given that Buckley had already sold the FM to Liberman and wanted to exit the market, he got a good deal ($2.5 million, including the real estate ... BTW, he paid cash) and he could do whatever he wanted to do with it.
Although I have never asked him, I think you're correct about his motivations.
Actually most of the "morphing" had already happened before then:
KJOI started in 1989 by replacing a lot of instrumental covers of hits with vocals, also reducing the MOR vocals as the added vocals were soft AC. The instrumentals disappeared completely by year's end (remember that brief period when they called themselves "Touch 98.7"?) and the changed the calls to KXEZ in early 1990 using the slogan "Easy Oldies". By the time Saul bought 1260 they had gone full ahead AC under the KYSR calls as "Star 98.7".
KBIG had done a similar transition to AC a couple of years ahead of 98.7, only they were more abrupt and went soft AC virtually overnight, just as KOST had back at the end of 1982. Both KBIG and Star went "hot AC" wirhin about a year of each other.
Of course, the other Beautiful Music stations had bit the dust ahead of KOST ... KWST went progressive rock on New Year's Day 1975 (then CHR in 1981 and AC after that, before becoming KPWR in 1986). KLVE (which had been BM since 1971, as KPSA) went soft AC in 1974 before being sold to Univision's predecessor and adopting a Spanish-language version of AC. KPOL simulcast its AM for the most part during its first two decades of operation, then went soft rock as KZLA in 1977, transitioned to Country right after KHJ did the same thing in 1980, and stayed in the format for a little over 25 years before becoming the ill-fated "Movin' 93.9" (KMVN) in 2006, followed by the sale to Grupo Radio Centro three years later and did a variety of Spanish-language formats under the KXOS calls before selling to Meruelo a decade later.
All of which probably made Saul happy about buying a station he could just "play" with to suit his own tastes and whims.