Hey Rene! Alles goed?
Which VSTs are you using for the synths? It sounds a bit lowfi (unintentionally) and... Cheap? For the lack of a better word. It could be that you're not optimizing the VST and synth sound that you're using. Like the pluck that comes in at 0:04, it sounds way too bright in comparison to the background. And the main melody playing at 0:29 is too buried, and lacks a bit of Attack and Decay. The synth playing at 0:41 is better than the other ones, but feels a bit timid and bland, but the base synth at least works for that part. The gating after 0:55 is pretty cool though, but could benefit from an automated filter or anything at all, just to make it a little more interesting.
The pitching "sirene" sound at 2:47 repeats a few times and I'm not sure if that's a sample or actually a gliding note or automating the pitch, but if it's the latter, then you could also make it go down, go all around, do some variations... That sound is pretty good but copy pasted it loses shine quickly.
Feel free to hit me up on the OCRemix Discord and send me a PM so we can possibly screen share a bit back and forth if you're open for that My apologies for the raw critics on this one - you shouldn't necessarily change the piece as it is, but it's always beneficial to go into a new project with a few extra tricks up your sleeve so you keep learning and improving.