After playing through your WAD, I decided to give my full opinion/feedback here.
Also, hello everyone! My first post here. I've been a fan of DOOM for a while now, but this is my first time here.
Overall, your WAD was really good! It had a very classic and simplistic feel, one that I've missed from a lot of WADS nowadays. The levels were atmospheric and claustrophobic, leading to some clever options for game play.
MAP03 was probably my least favorite from the set. The whole thing felt some what sluggish and confusing. I do appreciate the idea of the stage though, but at a certain point I had to noclip so I could just move on to the next map.
MAP04 was my favorite from the set. It was climactic as hell, and the atmosphere was incredible. Few WADS I've played invoked that feeling of immersion. However, despite using GZDoom as suggested, the dark segment in a certain section still felt almost unplayable. I had no depth perception or knowledge of enemies, and got mowed down immediately. It felt like a game of purely trial and error, and slowed down the pacing. Despite that though, the rest of the level was awesome, and that finale with the cyber demon was great.
The enemy placement in this WAD was clearly thought out, and makes sure you never let your guard down. Even when there's a ton of enemies, I found that the level design perfectly complimented this by providing cover and a place to plan.
To conclude, this WAD was incredible. Especially for someone's second project. Even with it's few issues here and there, I still had a blast playing through it. It felt classic and simple, yet fresh at the same time. I look forward to what you might make next!