The characters that he had planned for the Darkest dungeon type could fit easily as named-boss enemies and be used for the human, but we will see what the dev has planned..... Hopefully
As mentioned i know we are barely at 0.6 but that 1.0 is getting really close i do feel that he really hasn't pushed the game further to be even called fitting for release, hopefully whatever he does from 0.7 is actually really good with many more things as content and even gameplay
I think we'll see some more of those as enemies. Don't count on all of them appearing, hell don't count on half of them appearing unless we get unique boss enemies. So far we haven't had any boss encounters yet, or at least none that I know of. I think we might see them later on, so some unique human/humanlike enemies could return. And who knows, maybe we might get monsters or monster girls unique to them.
What I would put money on showing up is any monster girls. Dwarves will 100% turn up as generic enemies because
those fucking knife-ears elves made it in, so they'll likely be existing together just like the last game. Minotaurs and girl variants almost definitely, kitsunes and kemonos perhaps. It depends on whether the devs feel like adding lots of additional monster races for us to abuse like the orcs and goblins. Minotaurs will, but lamias/snakemen might not just due to the heap of fresh assets + animations they'd require. Everything else is up in the air.
As for why the game's not release-worthy yet, they remodelled a shit-ton of battle and placement mechanics and I imagine they're experiencing bugs with characteristics and reputation, hence why they've been temporarily removed. I know those two things don't appear to connect to each other, but game design usually requires you to wire up seemingly unrelated things into each other for the result you're after. You mess with one of those things, the game just might not work at all. Especially for a game as complex as this.