wow, i really like this! you have your own style, seems like a mix of acid notation and creo. I really love this progression and melody, but there's a little bit to work on on the composition and mixing side.
Some areas have the pitch slightly raised like 2:14 for example, and i can't really tell if that's intended, but it doesn't seem very necessary.
I love that chip-tune part at 2:02, and those acid notation/creo slidy synths throughout the song, although sometimes they're layered over other melodies that don't slide so it doesn't really fit.
The drops are really nice with a great use of sidechain, but they repeat for a little too long and you could try keeping it interesting by adding claps or high hats in the second half of each drop.
At 3:14 the sharps in those melodies should be natural so that they harmonise with the chord progression and sound correct overall, but apart from that they are a rally nice touch to the song and they add variety.
The wubs are also pretty cool, it would be great if you used more of them instead of just the drop start at 3:14. That little scaling thing at 3:26 also adds a really nice touch.
I like the smooth ending as well, although it's a little unexpected, maybe try adding some chords or bass to harmonise it.
Forgot to mention 0:48 sounds really nice with the chords and sliding synth. sorry this review is so messy lol
Ok so overall this is a really nice piece, and i love the design, composition and especially chord progression. It's just a matter of music theory by making sure all the notes fit, and variety, specifically rhythmically at the drop. Better than anything i've made xd.
Contact me if you want feed back for anything else you make and i'll happily review it, because this one was really fun to review and listen to.
Keep at it!
By the way i know you from samifying by BlowMypooh, you've probably played that level, if not it's awesome.
EDIT: Hmm, too keep it in tune if you can't hear it you just have to make sure everything stays in the same key, so it can be simple or complicated depending on what you make. I'm pretty sure the key is A# minor, It's mainly just the part at 3:15 where it goes down to A-Natural a few times. A-natural can fit, but only if the current chord for that area also uses an A-natural, which it doesn't, so an A-flat might fit it better. This might be hard to understand and it was hard for me to find out all the note names lmao. but it's pretty simple, just keep a scale guide or something open when making a song.