A wide array I would ponder a guess. I did not start listening to music until the mid 70's after high school, so a late bloomer? I got a bunch of hand me downs from friends then. What I listened to was 60's music, though it ranged from Frank Zappa to Credence Clear Water Revival, to BB King, and then danced with Jimi Hendrix, Deep Purple, and even a small collection of Waylon Jennings and Johnny Cash's version of Shel Silverstein's poem. I was more into reading earlier.
So, as far as characteristics? I think I made an effort to chase down poems I had read earlier that were released by various artists. I think if I chose a word or two for characteristics for 60's music it was transitional rather than breaking or transcendent. Breaking was the late 50's into the early 60's as jazz melded with blues and country added a bit and byte. Ballads mostly.
Late 60's heading into the 70's I ponder being transitional as a characteristic. Music could be said became more defined in one way with distinctions and loyalties to beginnings were more prevalent too. Like many guitarist were members of groups, yet they made their way back to their roots like Billy Gibbons, Frank Zappa, Eric Clapton, and even George Harrison and John Lennon too.
So, not being an expert of that era with overall music I think the biggest contribution was the fact of 33-1/3, eight track tapes, and mixing was becoming a defined science. Switched on Back was released in '68. The world tilted with that as the Moog Synthesizer fell into hands like Emerson and others. Switched on Bach caused a bit of a family Ruckus as mom bought it and dad was a die hard country boy. Tangerine Dream comes to mind too.
I'm Drifting oops!