Yeap
My suggestion was:
- Twelve faders (100mm)
- Twelve rotary pots (trim, pan, output level / user adjustability)
- Dedicated Solo / PFL buttons
- Transport controls (record, play, stop, pause, timecode, metadata / user adjustability)
- Power via Hirose or AA batteries
- Slate & Tone Switcher
- No plastic
- Not necessary the same size as R4+
It's not necessary to be the same size as R4+, based most cart mixers has 1U rack receivers or monitors installed to their carts. Cantarem II is a good example; but dedicated transport controls, trim pots and PFL is something crucial is a mixing surface.