This was a quick solve for me, unusually. 21a was indeed obscure but the wordplay seemed obvious and given 24d the solution wasn't hard to come by. I had not heard of one of the theme words (surely it must be the same one, buzzybee) and initially thought I had made a mistake but then google showed it was indeed the right theme word.
LOI for me was 8d oddly enough as the word is new to me (assuming definition is the last 2 words of the clue)