Petula Clark's "Downtown" is the most beloved British Invasion song that doesn't have a hint of rock music. Interestingly, it was inspired by Phil Spector, who changed rock.
The members of Led Zeppelin were influential before they even formed a band. For example, Led Zeppelin's Jimmy Page played on one of the biggest songs from the British Invasion.
British Invasion star Marianne Faithfull spent a lot of time with John Lennon while he was doing LSD. She said John's scary emotions came out in his solo work.
Aerosmith's "I Don't Want to Miss a Thing" was written by a songwriter known for writing romantic power ballads. The writer in question didn't think the song could suit Aerosmith.