A few posts back, soft rock album tracks were mentioned as a format option. I recall a few years when the format was tried and had some success. Most of these stations positioned themselves as the alternative to album rock radio of the day. The idea was to sound cool, current and such, just like the AOR format. There usually was about a 25% mix of 'hits' or singles, past and present sprinkled in the mix. Emphasis was saying a song was from a certain album, etc. Like AOR, the format tended to have a heavy rotation of currents, many of which would be the hit from the album the top 40 would play in a couple of months. Some stations used the moniker of 'mellow rock'. Many added a late night jazz show, say 10 to midnight, that worked nicely in many markets. Some of the stations had somewhat of a Mother Earth News slant with tidbits of information on things like gardening, alternative power sources and the environment. I suppose the more grassroots, more acoustic-based format better matched the earlier proponents of DIY and Green lifestyle.
In today's world I can't see it working but I'd certainly listen to such a station. The format may have been credited to KNX FM in Los Angeles. I do know the format was syndicated as KORJ in Orange, California utilized the format into the late 1970s. 102.9, billing itself as Magic, opted for the format around the mid 1970s in Dallas/Fort Worth. KAFM in Dallas even had a somewhat similar format at one point in the mid 1970s. It was one of the more long lasting formats on the frequency. Then KRLD's FM, you could count on an annual format change during most of the 1970s when frequently the format was automated.