Cryptic crossword No 665

Hello Pixlate (nice moniker - presumably three syllables?) Welcome to MyC and a very nice opener from you. I rattled through the first two thirds, really enjoying a lot of your wordplay, smooth surfaces and clever clueing. A few queries arose later in the solve - and could I urge you to publish Annotations to help me understand the ones i couldn't parse? Favourites include: 1a, 9a, 13a, 16a, 20a (lovely), 5d, 6d, 12d, 18d (splendid). Spoilers in Reply. Thanks. PM

Thanks for the puzzle Pixlate, and welcome to MyCrossword! You've created some lovely surfaces (particularly 8a, 9a, 10a, 13a, 15a, 16a, 25a, 1d, 4d, 5d, 7d and 18d all lovely), and some very satisfying wordplay (particularly: 9a a lovely construction, 13a very neat, 16a clean, 20a lovely construction, 21a neat, 1d a very satisfying clue, 2d interesting construction, 4d nicely constructed, 5d nice, 17d satisfying and 18d really lovely...