When reading 23A and 25A, they say,
"Missing suit". In the crossword you can find DIAMONDS, SPADES and CLUBS which are all suits, but not HEARTS. The only missing suit
Nice! I was originally trying to make words out of the letters that are inside of words that have two Is in them- miSCHief, aviONic, miSSing, liSALisa, iNit... especially after the "one one" answer for 20A, that seemed like a strong path. Nope! There are no good words to be found in there, hah.