Hmm, this sub-forum's looking a bit bare so far, so I guess something should be added to it. I said I'd do this months ago, but I finally got around to it recently. Looking forward to seeing where else you go with this!
This stage is a lot longer than the original, but more forgiving to make up for it. There are no longer any tight jumps over holes, and you won't be forced to commit suicide because an enemy damaged the stage, which happened very easily before. Other than an enemy knocking you down the hole, it's unlikely that you'll die in one hit. Because the main threat is a large number of small enemies, the health powerups should keep the player alive unless they make some big mistakes. This seems ideal to me for giving the player some close scrapes (this is Hard Type after all) while still easing the player into the game. The larger stage also provides more time to introduce different enemy types.
The level layout also feels a lot more involved, rather than being essentially a flat highway. The level looks great as well, and doesn't feel romhacky.
There's one path that I was confused about in the video, and I realized afterwards that there is a health powerup hidden at the end of the path. This area seems like it's a little too long with too many enemies for the health powerup to feel like a reward for exploring it. Instead, it feels more like the camera tricked me into going down a dead end with a bunch of enemies. From a design standpoint, I feel like this area is supposed to introduce some non-linearity, but from a player standpoint it's weird. This is the sort of area that feels like it would have a 1-up down it if lives were still a thing, but that's not an option for you, so I'm not sure what else to do with it.
Also, at 12:16, when you touch the left wall here, a wheel guy spawns from behind. This seems weird to me because it feels wrong for an enemy to spawn from the right when I'm moving left. My guess is that if you move that wall one tile to the left, the wheel won't spawn from behind like that, but I'm not really sure. Maybe this is intentional and you want to surprise the player though, IDK.