I was going to start a blind LP of this set but JB beat me to the punch, and I don't want to overload people's video-watching time...so I'll post my comments here as I play levels and read the developer commentary on pieguy's site.
Level 1 (Lock Picker): I'm not sure I've ever seen a Level 1 that can be cooked on the first move (though it's possible to die in Molecule on the first move). Nice little warmup level that forces you to be on your guard early but becomes more lenient later (I finished with 2 spare keys).
Level 2 (Inspection): Pretty simple. Just don't step on the wrong recessed walls. I like how the toggle walls toggle quickly enough for you to go through them all in a row without waiting.
Level 3 (School of Thought): I did see the hint that says you styled this after Madhav, but I wouldn't have been able to tell. I know, Josh, that you and I have both said that our design styles are quite different, and one way is I think you use many more irregular wall patterns in your levels, whereas mine tend to be rectangular. (Part of it is because I tend to lay down the walls for a section before filling it in, which has the drawback of limiting my options and sometimes making my levels feel kind of samey...then again, sometimes I find that the section won't quite fit my original wall plan and it turns out irregular anyways.) The way you used the irregular walls here, they make the solutions not stick out, which is nice. I felt a little clever solving the second section without the flippers...then I ran into the appearing wall when I tried to pick them up "just in case". Well played.
You say that Madhav's set featured "small levels that had one core theme"...that sounds a little like my design style except my levels tend to be large with one core theme.
Level 4 (Fade): I'm not as big a fan of blue walls as Josh is, but this level is scaled down to a moderate size, which is nice. I definitely got what you mean by subverting expectations...my experience was like "3 fake blue walls in a row! " in one place followed by "3 blue walls in a row...so they're all fake, right? Fake, *oof*, real " in another. I did like the loops and the time limit wasn't low enough to be dangerous. And...I think you've given me a blue wall level idea!
Level 5 (Dead Freight): Neat idea! I finished with a mere 9 seconds left...due to spending a while looking for the nonexistent "second usable block" in the maze before directing the first one to the bomb. I see you relaxed your normal avoidance of North and West thin walls; there are some concepts, like this one, that really don't work without them. *coughblockflickingcough* The title fit so well I didn't realize it was a reference.
-----NEWEST BATCH (3/6/2018)-----
Level 6 (Whatchamacallit): Interesting use of nails, and some normally "unfair" elements that aren't really that bad (thieves under blocks, for instance). So far the levels have forced me to be careful, but none have been notably challenging, which is fine as we're still early in the set.
Level 7 (All That Glitters): The name insinuated to me that I needed to avoid the yellow keys, which I did...until I saw that the exit was RIGHT THERE and I didn't need to be worried at all. I still avoided them just cause...and then I saw that I couldn't get into the southwest without picking some up. Ah, well. Definitely a more interesting maze to play casually if you go without, but would be interesting to optimize if you do use the keys.
Level 8 (Trick or Trap): Excellent, hit the first real challenge of the set for me! The bottom half of this level was a well-built, devious puzzle with a strict order of moving the blocks around. It was much harder than it looked at first and kept me occupied for quite some time. The top half, by contrast, had a ludicrously simple solution. Took me a little while to find it, though.
Level 9 (Discotheque): A nice cooldown after the challenge of Level 8. The extra chip drew my attention to the exit; I might not have found it right away otherwise.
Level 10 (Dip Your Hand in Felony): What a strange title...after Level 5, I expected it to be another Breaking Bad reference, but apparently not. I cooked the level early on because I didn't realize soon enough that you can't get a block inside the passage that leads to the teleports while a block is on the lower trap button...you have to start a block into that passage, then hold down the button...that's a bit hard to foresee. Also, I managed to conserve a recessed wall in the bottom-right section. The trapped balls in the recessed wall/block section were a neat aesthetic even if they don't signify anything. All in all, it's a decent variety level. (That's one of the other big differences in design styles between Josh and me--he frequently makes variety levels with no gameplay theme whereas I find it quite difficult to build a level without first choosing a theme to guide my decisions.)