Kind of taken for granted but all the stuff is there - the bright tone, the meta nature (Dorothy Malone telling Bob Cummings "AIP will buy the film rights", Vincent Price's cameo), the various subplots (Cummings studying kids, Frankie and Annette making each other jealous, bikers as a threat), colourful characters (Lembeck and his bikers, Morey Amsterdam's cafe owner, Jody McCrea's dumb friend, Eva Six's blonde bombshell, Dorothy Malone's sexy older woman, Cummings' anthropologist, Candy Johnson's dancing, John Ashleyh's more cynical friend).
The tunes are very good - "Beach Party Tonight", "Don't Stop Now", "Surfin".
There is variety in the female roles - Funicello is a good girl, but there's also a man hungry Rhoda (who can't understand why Annette doesn't want to have sex with Frankie), the shimmying Candy Johnson,
The musical numbers are done with tremendous verve.
Cummings was 53 (32 years older than Annette) but still looked good at the time - that would change within a year or so eg The Carpetbaggers.
Analysing John Ashley's role in this film - it's clear he's a kind of alpha in the group, suggesting Frankie dump Annette and also being the one not Frankie who entices Cummings on to a surf board (maybe this was to protect Frankie? Or Avalon may not have been available.)
The action screeches to a halt when Annette sings her ballad 'Treat Her Nicely'. But I liked how she was so protective of Cummings. (Also there's a moment where her character seems willing to sleep with Cummings, which is interesting. As is the implication that Frankie has slept with Eva). Because Funicello's character wants to be married an acts old she kind of matches with youthful (ish)Cummings.
Dorothy Malone doesn't have much to do but I liked her and she's sweet shimmying along to 'Tell It to the Moon'.