chat-up line; pick-up line; (loving) words
cliche; platitude; formula; set phrase
undisputed; entirely; perfect
clincher; pick-up line; honeyed phrase; telling phrase; phrase that brings someone around, esp. in personal relationships
catchphrase; promotional line; slogan
sales pitch; sales lure; catchphrase
sales message; sales copy
witty (happy, apt) remark; well-worded saying; epigram; aphorism