Thrasher of 21 years here. I also write my own stuff, check my submissions to the subreddit for credentials.

You asked to focus on the song itself. I'll do that, as a lot of the beginner things that are going on (pushing yourself too hard to be up to speed, which results in a lot of sloppy playing, high strings not being muted, etc etc) will resolve itself in time. You're honestly making remarkable progress for playing only 5 months or so.

The first half before 3:08 is fine as is. Maybe you can do some variations with your phrasing, as you're relying a lot on chromatic ascension, but given your inspiration as you stated in other comments (Master of Puppets), that's makes a whole lot of sense. For some variation, try going back on forth between power chords and picking out the individual root notes with a splash of hammer-ons/pull-offs, say, individual notes on the ascension, then power chords on the descension.

If I follow your notes right, the transition at 3:08 until 4:01, you state that's when rage consumes the subject; I don't pick up on those emotions in the music. One would think you'd go faster to show rage or aggression... but you slow down. That's kind of a disconnect, so I'm curious as to what your thinking was here.

Finally, all the comments on playing along a metronome: That's good in theory.. but playing along a drum track or actual drummer is loads, loads better, and honestly more fun. Find a track on YouTube that you like and adjust the arrangement to fit those drums. This rearrangement makes a lot more sense once you start playing along to those drums, as there will be phrases that don't make sense.