I put a highpass filter on the kick thats the reason for the flat sound at the beginning. (I changed it now) Apart from the flatness, what about the dynamics, stereo width, compression and overall loudness?
You have a really nice melody there. In my perspective, I feel that the parts before the drop is kinda thin. I would try to cut Back on the highpass and cut a little on the high ends. But that is all personal preference. Really great track imo!