"Kokomo"

Last night, I figured out the chords for "Kokomo."  The song is in C major, but there's a D major chord at the end of the line "That's where ya wanna go to get away from it all."  The F# in the D major is an accidental, and so there's a musical sense of foreignness that matches the notion of "get[ting] away from it all."

I also noticed that "go" in the line "That's where we wanna go" is sung with a melisma (C G A), musically giving a sense of movement.

"Kokomo"

For whatever reason, I started thinking about "Kokomo" this morning.  The only album I have it on is the compilation Sounds of Summer: The Very Best of the Beach Boys, which I haven't listened to since last September.  In any case, I realized something about the first section:

Aruba, Jamaica, ooh, I wanna take ya
Bermuda, Bahama, come on, pretty mama
Key Largo, Montego, baby, why don't we go

The listing of places (a rhetorical technique called cataloguing) recalls the earlier Beach Boys song "Surfin' U.S.A." specifically these two sections:

You'll catch 'em surfin' at Del Mar
Ventura County Line
Santa Cruz and Trestle
Australia's Narrabeen
All over Manhattan
And down Doheny Way

At Haggerty's and Swami's
Pacific Palisades
San Onofre and Sunset
Redondo Beach L. A.
All over La Jolla
And Waimea Bay

I referenced the lyrics found here, although I'm dubious of their accuracy.  It's clearly "You'll catch 'em" rather than "You'd catch 'em" and "We'll all be planning out a route" rather than "We'll all be planning that route."  I also referenced the Wikipedia page to verify and correct some of the locations.

The music for "Surfin' U.S.A." was taken from Chuck Berry's "Sweet Little Sixteen," so it seems that the notion of cataloguing places is also taken from Berry's naming various locations in "Sweet Little Sixteen."  I'm not sure whether the catalogue of places in "Kokomo" was meant to be reminiscent of that in "Surfin' U.S.A." (or "Sweet Little Sixteen"), but it is the same technique.