Hey buddy,
You’ve got some good pedals there.
Firstly, on your Octabvre Mini, turn the tone knob all the way to the right. This will give you the most harmonic-rich, honky tone to start with.
If that doesn’t work, my main suggestion is to add an envelope filter between the Mastotron and the chorus. With the right settings, this will give you some squelch and bite that should really help you be heard. Putting the envelope filter after the fuzz/distortion keep the sound tight in my experience, but for something a bit more unruly try putting the filter in front of the fuzz.
My personal favourite standalone envelope filter is the Mr. Black Fwonkbeta - it’s compact, simple and can get very nasty! Filters are very much a matter of personal taste so maybe watch some demos online to get a feel for what’s out there.
Failing that, if you want a one pedal solution, I’d highly recommend getting a Source Audio C4 synth pedal. It’ll give you almost any synth sound you’re likely to need and has the potential to take over your octave, fuzz and filter pedal needs all in one compact unit.