Yes and no. There was a lot of reworking and changing of earlier content, fiddling with mechanics and switching things around.
However, while the end result may or may not turn out great some day, the process certainly wasn't. I haven't played for a few updates now, so I can't comment on the current state, but for a long time many mechanics were broken or not working as intended. Options that were previously available suddenly no longer worked and vital subsystems, like the forge, happened to break completely without the devs even mentioning it until patrons pointed it out.
I'll have to take your word for the current version being of "consistently high quality" but if the changelog in the OP included all bugs and bugfixes it would be the length of a novel.
I do agree about the art and writing though. Quality stuff, even if the vast majority is aimed at subs and cucks.
That is also largely fair, but I'll also disagree just a bit.
The game is a bit buggy, and the underlying mechanics have been overhauled, but they're still not great. I like that the skill checks now are a bit more simplified from their earlier heavily d20 inspired iteration, but they're still not great. But earlier content has not only been reworked to be better written, but fit more logically within the narrative structure; especially so with the intro content that occurs before Rowan is given free reign and pointed at Raeve Keep.
Now because there is so much content, and most of it has so many layers of dependencies (I've played around with debug using UnRen), I understand how keeping so many spinning plates in order at one is a daunting task. That's not an excuse for game bugs, but an explanation as to my understanding as to why they happen and why I don't let them bother me as much.
While there is certainly a sizeable amount of BDSM content of all stripes, I'd quibble with labeling it as the 'vast majority', especially so content where Rowan is a 'cuck'. Cause, he really isn't your typical jilted lover. If you're looking for an actual cuckold experience, where the MC gets soul crushed by watching their rival fuck the love of their life in front of them while they're impotent to do anything to stop it (e.g. A Promise Best Left Unkept, Babysitter, Alansya Chronicles: Fleeting Iris, Swing & Miss, etc.)? That content isn't in SoC. Sure, there is NTR content, quite a bit of it. But you can see that content by neglecting Alexia, focusing on Helayna, and just being an inattentive husband; let alone a right bastard in your own right.
Rowan isn't limited to being a sad-sack cuck, because Rowan
FUCKS. While Alexia falls into Andras or Jezera's orbit, Rowan can be fucking damn near everything else that walks near him. Goblins, orcs, dryads, elves, succubi, captives, nobles, nuns, adventurers, driders, prostitutes, his forge master, his secretary, the brothel's madam, an anthropomorphic spirit-wolf, and even a fucking will-o-wisp. Rowan can be an absolute manwhore if you want him to be, without being submissive, whether or not Alexia is fucking around behind him. There are plenty of options to be a sub, but also to be a dom, or to be gay, or even just be vanilla as hell and faithful to Alexia in the face of corruption (but if you do, you probably play boring Paladins in D&D and you should be ashamed of yourself

).