The Planning Board may vary lot areas and dimensions,
yards, and setbacks for the purpose of encouraging and promoting flexibility,
economy and environmental soundness in layout and design, provided
that such standards shall be appropriate to the type of development
permitted. However, when new lots are proposed in built-up subdivisions,
the Planning Board shall consider the dimensions, setbacks, road frontage
and other features of existing lots to promote a logical coherence
among the proposed and existing lots.