On one hand, a prevailing strategy for thermally-activated delayed fluorescence (TADF) emitters involves minimizing the (positive) singlet-triplet gap by tuning the spatial separation of HOMO and LUMO on distinct and often orthogonal fragments in donor-acceptor-type compounds. On the other hand, both multi-resonance TADF emitters and the emerging family of inverted singlet-triplet gap molecules rely on spatially proximate though non-overlapping frontier MOs which are found in specific alternant and non-alternant planar ring motifs.