I find that HTML games tend to come in two completely unrelated flavors: "real porn" with lots of images & animations but low-effort writing, and text-based adventures with good writing but little to no art. I'm a fan of the latter and can recommend these two:
Accidental Mind (slow updates, but lots of content and the dev is definitely still active)
Unholy Arts (updated...today, apparently. Nice.)
I haven't finished
Inner Empire yet so I can't give my opinion, but it seems to fit the bill and a lot of other people recommend it.