Ignore what the plug looks like. Reading plug color really only applies to WFO ie flat out under load. That doesn't tell you anything about idle mixture. Set idle mixture to give you the highest idle speed and the best response as you crack open the throttle. Anything else is a distraction at best and misleading at worst.
Fix the electrical system first and then set points gap and timing and after those are spot on, then think about tweaking the air screws.
Fix the electrical system first and then set points gap and timing and after those are spot on, then think about tweaking the air screws.