Finished the game.
I need to sleep on it, but overall I found Signalis to be underwhelming given the hype. It's unique and weird (and impressive considering it was made by only two people), but the story didn't wow me as much as I'd hoped. There are plenty of cool ideas and worldbuilding nuggets, but the narrative itself didn't grip me.
Gameplay-wise, it was fine for survival horror. Aside from a couple radio headaches, I found the puzzles to be well-designed.
Biggest complaint overall is the controls/interface... Why must I look away from someone before I can talk to them twice? Why must I look away from a door sometimes before I can open it? Ugh.