If you hit a wall, maybe think about introducing some sort of white noise style build. Perhaps maybe resample that bassline, chop up the pieces and throw each one in reverse or something. Add in a section with a different "space", maybe more reverb, or something with a high-pass filter.

You should try to introduce some dynamics if possible!

Nice! Hopefully you can expand upon it. Take the overarching portamentos and cut them up/warp them, introduce a double time section maybe, add in some filtered sections to create some dynamic range in the piece.