I agree, much better indeed. As for the formula, mix the next batch to look like the first, and if it's close enough, it's good enough !
There's too much b*ll*cks talked about exact colour shades sometimes, when in reality, apart from the 'scale effect', even modern-day aircraft can have a variation in shade due to many, many things.
The basic rule is - "If it looks right, it is right" !