Have been reading remarkable book by Eleanor Cook, Enigmas and Riddles in Literature (led there by way of her writings on Wallace Stevens).
In a chapter on modes & genres, she contrasts ancient charm poems with riddle poems, & discusses how charm as a mode (hypnotic, mellifluous, enigmatic, highly-wrought) held sway during the 19th century (Keats, Poe, Tennyson) "up until about 1915". Its counterpart, the riddling manner, she sees as akin to the "line of wit" - cites Dickinson as one exemplary "riddler".
I guess the proverb falls somewhere in between. Charm poetry aims to cast a magic spell; the proverb or adage is gnomic wisdom, hortatory & didactic; the riddle confronts the reader with a quiz-problem. (& maybe charm/riddle ends meet in an enigmatic middle.)
The riddle shades over into the enigma, which is not quite so cut-&-dry : edged with profundity & mystery. In terms of rhetoric, the enigma is a simile, or metaphor, in which one half of the figure is hidden, missing, encrypted.
Cook suggests that some of the disputes over style in poetry are rooted in this generic (or modal) distinction between charm & riddle - & that the disagreement is mostly a matter of taste, rather than quality...