A side discussion developed about the true meaning of the term mean aerodynamic chord, which lead the originator of the thread to feel that it had been hijacked, so he deleted the thread.
Given the way he worded his questions, I think that what he needs is a basic guide to how to take a plane that works and copy its aerodynamics to another plane. Basically, the guide would let someone know what's important (aspect ratio, areas, moment arm distances, etc.), tell how to measure things (MAC to MAC, which is what upset the OP), what's not so important aerodynamically (nose length, although it matters to balance and possibly in a minor sort of way given whatever aerodynamic effects a prop has).
I'm walking a minefield here with the usual denizens of the engineering board, because even before the OP got upset with the MAC discussion it was obvious that what he needs is a simplified guide, while the usual crew here tends to get into all the esoteric little details. Worse, to some extent the minefield is justified, because this is aerodynamics, which means that some of those seemingly little, seemingly esoteric details actually make a difference.
For all that, I think one could come up with some guidelines that would let an aerodynamic beginner start with a set of plans for an Impact and a goal of (for example) designing a semi-scale stunt Dewoitine D.510, and do a good enough job of transferring the aerodynamically important features of the Impact to his frenchy Warbird that at the very least he's encouraged not to stomp the thing into the ground after the first flight.