Another entry in the list of themes it is more difficult to explain in words than just to experience during the solve, is as follows:
Two phrases, each of two words, are juxtaposed, in that the second word of the first is a homonym for the first word of the second, and similarly, that the first word of the second is a homonym for the second word of the first.
Many words in the service of blogging.
Thusly, 16A: Prince, e.g. (MALEHEIR) next to 25A: Stamp on an envelope [and 16-Across flipped] (AIRMAIL). I like that each flipped answer is the next to the right and down, making a logical progression, rather than having to search through the grid.
I was uncertain about PLAINTOE, but it Googles well. THYMETEA, as well, comes up readily on my arbiter of widely accepted use.
More impressive is the collection of long down answers: there are eight of length 8 or longer. I am particularly fond of 32D: Signed, sealed or delivered (PASTTENSE). I was not thinking along those lines at all!
39D: Wasn't upright, say (SLOUCHED) is a great clue.
I very much enjoyed this puzzle. It's odd, but it's pleasing. And it has RYE.