Act 1:
Whoa, I sure didn't expect you to get this creative with the sector scenery. While the texturing is still repetitive and you still need custom textures, it looks much better now, and I like the small eye-catchers lying around just about everywhere. You really showed how competent you are with sector-based scenery, and I want you to use it more often in other zones. The thok barrier here can be a bit weird at times, I should never be able to actually be above it because it looks weird if I am blocked by an invisible barrier.
After the introduction section (which you might wanna spice up a bit with some more basic platforming, you could expand that water pool for instance), I get to a room which I already criticized before. It's too mazey, and you didn't do anything to change that. The basic concept of it is OK, but you should make it absolutely clear where that spring is, I don't want to search for it. The upper section could also benefit from wider gaps, I hardly need to jump.
At the path split, one option consists of a waterslide that doesn't make you do anything. It's there, but you only have to wait to progress. Put some obstacles and also make that path a bit longer than the other one. The new path is quite good, though I always feel like the boxes should float up and down, for some reason. The shield also requires no effort to get to. In the outside room after the slide, there is a very cool ship that you unfortunately never use for actual gameplay. What stops you from having a port section that involves gameplay with these boats. By the way, the secret that involves the ship is missing a colormap in the water. Speaking of colormap, it's still too dark.
The flooded room following next is also maze-y, as well as sheer redundant, thanks to lots of springs and more weird thok barriers. In the following room, we get a path split, but both paths don't really contain much gameplay. At least the left path has some cool bridges, but the player never gets to touch them. Those water floor sections are now technically filled up, and the visuals are quite interesting, but it's still more or less running.
The section where that weird "footprint" is is too cramped and also feels like a maze, due to several dead ends. The crumbling wood in the room after that doesn't really provide much of an hazard, they should be used as stepping stones over a pit or something. The broken hydrant that swings you up is a cool idea, but it could be used more creatively, for example by forcing the player to swing from hydrant to hydrant. Also, upwards current is broken, so implement it so the direction you face is the right one. The upper section after that feels weird due to the thok barrier and is useless otherwise.
Act 2:
The beginning still feels like it could host an alternate path or at least some secrets, but it doesn't. The water is still way too dark, I don't even know it if you raised it or not. I like how you installed the first alternate path exactly where I suggested it, and I still like its placement that kinda resembles the classic Sonic games: You can only enter the path if you pay close attention.
The path itself is cool too, but I feel like you didn't do nearly enough with the rope platform gimmick (even though it's actually just a normal platform, the rope makes it feel special). For example, I can skip the second one entirely. The pool after than is useless anyway, so I suggest replacing it with some more complex iterations of the gimmick. Zoom Tubes are a very cheap way out anyway, and since the other path takes much longer anyway, you could fill the entire length of the zoom tube with content (even if it's just a straightforward linear room, you could use the hydrant hopping idea here perfectly). I like the box climbing sequence after the Zoom Tube, even if it's rather basic platforming, but I can take some basic platforming every once in while.
The old path still looks rather plain, especially in the underwater area, make it feels a bit more ruin-like, by making it overgrown by some plants for example (excellent excuse to use some DSZ textures to spruce it up right there). That applies to the zone in general (even if the open, dry-land sections probably should remain city-like). Also, the flooding button rooms at the beginning of the path are still kinda uninteresting, because I just need to climb a staircase. Make me do some real platforming please.
What I really don't like is how the paths come together. You know, I press a button to get into another room where I press another button. Totally lame. You know what? When you go forward in the waterslide section at the loop, you will end up back at the start of it. Instead of doing this (it's also lame), make the new path end up there instead (they're separated by only 300~400 fracunits anyway) and make the former looping sequence takes you to a new path either use a teleport or move all those control sectors and use the inside space, your choice). That would be much better, and there really should be another long alternate path anyway.
Now the waterslide section itself: That could use some more action apart from the basic spikeball dodging. Also, the loop still isn't as amazing as you probably seem to think. In fact, it's ugly and boring. After the (admittedly cool, and you did it BEFORE Blade) wave room, we get to a path split that offers a choice between two mazes. The old one from the last version still sucks and should be purged/replaced, but the new one has potential and just needs some tweaking. You probably didn't intend it to be a maze, but its layout lends to that. The Elemental Shield is more noticeable than the button, and the door that it opens is also hard too see. I'd recommend not using a button at all and restructuring the room so that the exit is easy to see but hard to get to (e.g. platforming). I'd absolutely love to see a room where the water periodically rises and falls together with some loose boxes, while some stationary ones remain, so you'd have to hop back and forth between the moving ones and the stationary ones. Maybe that would fit here.
The courtyard where both parts meet looks cool, but not cool enough. Try having some sort of mini-garden here that grew wild after being abandoned (or think of something else, you might not actually want to implement all of my ideas as they are...). I also want the point where I jump down to the streets to be a balcony. I sort of missed the streets that mostly showed up in Act 1, maybe you'd want to have them show up somewhere earlier in the second act so the theme feels more consistent. I absolutely adore the car and I really want you to modify this room so I have to jump across a few cars to avoid some pits. Those cars need more exposure, and the room would otherwise be flat running.
The train station, as cool as it looks, still needs some gameplay. It's a bore to run through, especially as Tails. When you can't think of anything, make it a waterslide and put some more obstacles (preferably slightly different for both sides of the station). Guess that was it for this act. I sure demand a whole lot from you, don't I? O_o
Act 3:
Nothing to say, except that arena should be completely surrounded by buildings. It looks weird if I can see the sky to my sides when water is rising up around me. Gives me feeling of "What kind of invisible barrier is holding all that water in here?"