Had some time free to finish up, so last post for the Casual Mode playthrough!
Dungeon 15 was shockingly easy. Sure, Dungeon 14 felt too easy for how seriously I took it, but Dungeon 15 honestly felt like I could've beaten it with my team from two dungeons ago. I had revives and tons of healing items, and I hardly needed them; I didn't so much as break out the Orange/Red liquids for full heals before defeating the boss. Of course, part of this might be stat accumulation from this being an all-titles run? Gradual move replacement wasn't much of a downgrade in many cases, and the ability to swap movesets made it feasible to replace moves without it being a big deal. The level design was reasonably straightforward with chests in predictable locations, and many of the enemies came in singletons... which could often be defeated two at a time, using the overlapping glitch I reported earlier (the barn is a case where this feels intentional; just walk straight up the center line and you only need to fight half as many battles. Between the pills and easy fights, I capped out quickly here, well before everyone was trained, partway through my first run (and found more pills after that to save for later!).
When I found the boss, I defeated it in exactly one move cycle; open by debuffing special defence (with Ribbon Tie) and murder with existing single-target specials. With its low HP and meager defences, there are individual monsters from previous dungeons who felt scarier than this boss; I didn't even need to bother debuffing its offensive abilities like with most bosses. Its actual attack was unimpressive, and even the scary debuff wasn't all that scary. Getting everyone fully-trained took more effort, of course, but the all-pet team beat the boss just as easily; debuff regular defence (with Moo and Tail Whip), and quickly kill with Backwards Kick and Crunch. Given the availability of multiple attack debuffs and stacking attack buffs in the pet moves, this boss could've been MUCH more difficult.
Thematically, this was definitely a hit with me. The transformation dialogue really helped sell the theme here; it definitely added a lot to this dungeon! I also really appreciated the infinite section for helping train the titles, since 1000 steps would be a lot if I needed to make them in more confined space. The semi-repeated level layout reminded me of Dungeon 10, in a good way; much like with hypnosis, repetition felt exactly on-theme for a dungeon based on training. The only downside was the enemies, which didn't feel different enough despite their cute costumes.
A couple minor bugs... Kitten's "Purr" move wasn't usable for some reason; whenever I ordered a girl to activate it, it instead selected the most-recently-successfully-used move by that girl and did nothing. Also, it's a minor graphical issue, but when fully-transformed, Pig has a skin-toned bald head from behind, instead of the pink pig hood.
Dungeon 16 was, of course, just a boss rush. The first two forms actually felt like serious bosses (unlike the 15 boss), but serious boss tactics worked just fine, and I beat the first two forms with no losses. I nearly ran into trouble with the final form of the boss, but just being able to have Madoka Inner Focus repeatedly and use Holy Shot when she could was plenty, especially since Mami and Kyouko got their debuffs in before going down. The post-boss dialogue felt a little anticlimactic, especially with the absence of a final cutscene. I was expecting something like Homura apologizing to the group and explaining what the whole game was about (sort of a less-private post-14 scene; Homura obviously has some explaining to do about why she's repeatedly been sending the girls into fetish dungeons), but instead there was just nothing, which was a little disappointing.
Another quick sidenote; Invoke Hypnosis II has an image glitch, in that bare arms are visible outside the straitjacket. Not a huge deal, but it bothered me a bit.
And... that's it, I guess? You'd mentioned previously that there'd be an update out around now for bugfixes and adding new content to Hard Mode, is that still planned with the Itch demonetization thing?