PitchBend is OK, this is what you need. Mackie Control is using PitchBend to control 8 faders 1 Master fader. Map your faders this way:
1st fader: PitchBend, MIDI Channel 1;
2nd fader: PitchBend, MIDI Channel 2;
3rd fader: PitchBend, MIDI Channel 3;
9th fader: PitchBend, MIDI Channel 9;
In Cubase add Mackie Control Device, and set your MIDI Device as an Input. Disable MIDI Input of the Generic Remote, to don’t double remote devices.
Now, you should be able to control first 8 channels via your device, plus the Master Fader. If you have any buttons on your MIDI Controllers, you can assign them to Bank (or Channel) Left/Right, so then you can even switch banks/channels and control all your tracks. Be aware of limitations of non-motorised faders. For this Generic Remote is better, because you can use the pics-up mode.
Maybe you can combine it and use Mackie Control just for the Master Fader (PitchBend on channel 9), and other tracks control via Generic Remote and MIDI CCs you already have.