Well, I guess it's my turn to offer my two cents.
LEVEL 1
---
Right off the bat I notice that it's in SA Mode, and I'm facing the wrong direction for some reason. I begin heading towards the bridge, and I notice Sonic's weird walking animation. I try to ignore it and continue. I make it past that first island with the 3 robots with no problem, I just run past them. I get to the broken bridge part and take the springs over the gaps. I hit the speedpads along the way, and noticed that they really didn't provide much of a boost. So, I make it to the second island, and this is where I start to have troubles. I run towards the robot and get ready to attack him, but instead my homing attack decides to go after the large grey wall next to him. So, I sit there for a while, eventually the robot shoots me down. I try to turn and attack him, but SA Mode's controls send me flying off a cliff.
So, I'm back at the beginning. I go through the stuff above until I make it back to that island. This time, my Homing Attack actually hit him. However, I'm suddenly hit by something else. Apparently there was another enemy hiding behind the box. So, I go to attack him while I'm invincible, but the Homing Attack goes so slow that he kills me before I hit him.
Last life, back at that same island. This time, I just run straight for the box and try to jump past the robots and over that wall. Well, due to bad control (SA Mode again...), I go flying off the other side of the island.
I restart, I make it back to that island and jump onto the box and over the wall. I just barely stop myself from going over; there really isn't much room there for landing. I notice the giant green thing and figure that's what my Homing Attack was trying to get to back on my first life, so I jump at it. A new path appears over the water, so I try to jump on it, but SA Mode has other plans. As you can guess, I miss and fall to my death.
So now I'm on my 2nd life on my first restart, and I decide to turn off analog since it's giving me so much trouble. I'm starting to get annoyed now, so I just try to speed back to the part I was at. I get to the broken bridge and try to just thok over the pit, but the slow Homing Attack doesn't give me enough distance.
3rd life, 1st restart, I run through the stage like normal until I ge to the second island. I'm unable to stop myself after hopping over the wall, and go flying into the water below.
1st life, 2nd restart, everything's normal until the 2nd island, I decide to just spin into the enemy on the opposite side of the island. I kill him, then I hit the wall, which suddenly breaks. Yeah... It would've been helpful if there was something there to tell me that the wall was breakable, then I wouldn't have been trying to jump over it. I contine like normal, hitting the green thing and getting on the weird glassy conveyor belt (I'm guessing it's supposed to be a rail?). I finally make it to the starpost; I head over to an area with a small green FOF with a line of rings above it. I jump to the line of rings and hit the lightdash button. I go flying up into the air, where I see nothing but a jetty-syn who is just sitting in mid-air doing nothing. Being unsure of what I'm supposed to do, I fall to my death.
2nd life, 2nd restart, luckily I don't have to start at the beginning again. I lightdash up the line of rings again, and try to land on the Jetty-Syn, thinking that maybe you guys SOCed it to be different or something. Sure enough, I get hurt and fall to my death again.
3rd life, 2nd restart, I lightdash up the rings and land on the side of one of the pillars. I realize that the pillar is too low for me to Homing Attack the Jetty-Syn, but I try it anyway. Death. At this point I'm getting very annoyed. so I shut the game down for a while and go ask about what I'm supposed to do at that part. I was told that I had to Homing Attack the vine, which I hadn't thought to do since FOFs aren't Homing Attackable. I figure you must've put an invisible object on it to make it work like that, so I give it another go.
1st life, 3rd restart, I make it back to the starpost without much incident (except for almost falling off of the rail). I Homing Attack the vine, fly up into the air, then Homing Attack the Syn. I start moving towards the closest island I can see, but I begin falling before I make it there. I noticed while I was going up that you guys must've put a per-sector gravity special in the area above the Syn, since I started falling the instant I moved out of that area. Dead again.
2nd life, 3rd restart, Homing Attack both objects and make it up to the right area. I take out the two robots after getting hit a few times, lightdash across the ring trail to the spring, and finally beat the level.
So, yeah, it took 11 lives for me to figure out how to beat the first level. That should be telling you something. If you've never played Next Gen, you wouldn't know how a lot of the stuff in this level is supposed to work. Assuming that the player will know what to do is REALLY bad level design. You need to ease the player into learning how to use some of the more complicated things, give it to them earlier in parts where screwing up won't cost them a life.
===
LEVEL 2
---
I quickly disable analog, not wanting to relive my first few lives of Level 1. I notice some glitchyness right at the start: the level is too open, SRB2's engine can't handle the long-straight path. Ignoring these things, I start to run through the level. I notice a Jetty-Syn sitting near the start, but that's the only enemy I see in the entire level. I run past it and hold forward. I continue holding forward, occasionally jumping, and... holding forward. The level is really quite bland, there's nothing going on. You're just holding forward and hopping from platform to platform. I know we usually say that SA's levels only require you to hold forward and occasionally jump in order to complete them, but we were just exaggerating. In this level, it's really quite literal. I mean, you have to turn about once or twice, but that's it; the rest is just holding forward.
===
LEVEL 3
---
As if holding forward wasn't bad enough, now I'm being FORCED forward. Now I don't even have to hold the forward key, I just have to occasionally jump. Seriously, I beat the level by pressing the spacebar (my jump key) 4 times. I had to move a small amount after running into a wall, but the rest was just jumping.
===
LEVEL 4
---
This is Level 3, now with 50% more glitchyness! Again, jumping was about the only thing I had to do. I only had to move when I got to the part with the THZ turret, and the ending part since the whole automatic moving stopped.
===
LEVEL 5
---
Techno Hill Zone, Act 2, eh? You need to fix your header. At least this level allowed me to move, and wasn't entirely composed of a straight path. It was still very bland, not having much of anything in it. I just made a quick run straight to the exit, not meeting much resistance at all.