Thanks to Everyman. Fun puzzle, maybe not quite up to the level of the last three, which were outstanding.
17 was my COD! Also liked 6 and 21 (good surfaces) and 11.
FOI 2. LOI 8, which took a long time to figure out.
Didn't see any alliterations or rhyming pairs (not counting the 2 downs with identical 3-letter endings). But some other traditions: "primarily", homophone, foreign phrase.