I don't know how it translates to full-size,...but.....model helis are very critical on blade-balance.....chordwise is just as important as lengthwise,and , of course, the perfectly -balanced blade should weigh exactly the same as any of the others on the same rotorhead.
When you're running 2,000 RPM headspeed, with almost a 2-metre diameter rotary scythe that's as fast and twitchy as hell, you want it right!
The bigger they are, the easier to fly,(inertia and gyroscopic effect) but the more important accurate dynamic balance, track and good bearings in the system.