I wanted to play more than one episode before laying out my thoughts, so I went and played through the whole first week's worth of episodes. Honestly I'd play each one as soon as the clock hit midnight because I just wanted to see what happens next!
I'm waiting with great anticipation for the next episodes (waiting a whole week now for each one is gonna be killer, no pun intended)!
First thing's first -- I really love the music. Especially how every song kinda has that same theme in it if you listen closely. It's also nice just to listen to when you're thinking about how to solve the puzzles. The art is well-drawn. It's not the usual anime style, so it stands out a bit more as unique and memorable. I especially like Sent's 3D-ness. And the writing and presentation are both solid so far.
These first few puzzles haven't been too difficult, as I'd expect from the opening stages. There were a few times where I felt the hints were too extreme. The "greenhouse" one in particular was a dead giveaway. On the "ten" puzzle, I spent a long time trying to make a diagonal 10 out of the pieces, and then when I asked for a hint someone just flat-out gave the answer. After that I became cautious about using hints, so for the Celsius puzzle (it's spelled wrong on the Episode Select, by the way) I decided not to use any. And I got it right, but only because I paid attention to the title. Still don't know what the other two letters stood for, I just guessed like Ink did!
But the latest puzzle really had me stumped for a while. I didn't want to use any hints, so I spent a lot of time thinking about it. Eventually I used them, but they didn't tell me anything I hadn't already figured out. I'm really just not sure how Rae figured out which button should have been pressed first, since the first two buttons are identical when rotated. Was there a way to figure that out on my own, or did I need to use a hint for that? I felt like the hints in this puzzle were more evenly spread, not too spoilery, plus a skip button appeared out of nowhere in case I got stuck. And I actually did skip the puzzle, then went back and got it. I realized that even though I had read all the hints, I accidentally pressed the buttons in the wrong order anyway, so when I went to do it a second time I got it in a matter of seconds. So that was the most confusing one so far, but it was a nice challenge. I think that one had the right amount of difficulty, the hints just enough to help you get started but still need to apply some thinking to solve the puzzle.
Regarding the characters, their trust levels (for me) are all roughly the same, but I've usually been favoring Aether over the others. And as for the story, I think it's developing nicely. Every episode ends with a cliffhanger, so I'm enjoying the pacing. I also like the reminders at the beginning that tell me what happened last time. The structure does get a little repetitive though: recap, move to the next room, solve a puzzle, cliffhanger. Maybe it'll be changed up in later parts? Each episode also seems a little too short, but that's usually a good thing to hear!
Anyway, I suppose I'll have more things to say as the story develops, but congratulations on releasing everything so far! It's a lot of fun!