Vernier mixture for sure. If you can build an airplane you can certainly build and then modify, your own two lever quadrant. Or simpler yet another vernier for the prop and a single lever throttle. I have 10 years on my two lever plus vernier mixture and like it better then any of the manufactured ones. I have used the van's unit and a few different aftermarket products but prefer my own. Or maybe it just the personal satisfaction that I prefer!
Tom Martin RV1 pilot 4.6hours!
CPL & IFR rated
EVO F1 Rocket 1000 hours,
2010 SARL Rocket 100 race, average
speed of 238.6 knots/274.6mph
RV4, RV7, RV10, two HRIIs and five F1 Rockets
RV14 Tail dragger under construction #153
St.Thomas, Ontario Canada, CYQS