I was kinda expecting this to be pretty "meh", but hey, this was actually a pretty alright (first?) level. I appreciate your choice of textures and aesthetics. I noticed that you mixed in a bunch of different sector specials such as fake floors, teleports and FOFs in your level. You also managed to avoid putting "water floors" in, which is a first timer trap that many new mappers fall into. There's multiple paths And is that a skybox I see? It's a pretty good one.
It's true that this is a flat level. However, I'm not overly bothered by it, especially considering this could very well be your very first level. I'm not really a fan of 2D in most cases, but I can easily forgive it for being as such because you at least tried to make it compelling to play. The only gripe is that in the first 2D section, while I do applaud you for trying to balance risk/reward, the turret might be a little bit overkill for the sake of a single ring box item. Either make it worth it to go after those difficult to reach things, or tone down the hazard so that going for the thing doesn't just result in a net loss of rings. That being said, the method for getting the special stage token was very clever, and I love that you understand why and how and why it's supposed to work. I'd suggest that you keep experimenting with linedef executors in the future, you seem to have the basics down and then some.
Amateur or not, this was very well crafted, and I'd like to see more from you!