We introduce pathway complexity on a multicomponent systems level in chemically fueled transient DNA polymerization systems, achieving autonomous evolution over multiple structural dynamic steady states from monomers to dimers, oligomers of dimers, and randomized polymer structures before being ultimately degraded back to monomers once the fuel is consumed. The enabling key principle is to design monomer species having kinetically selected molecular recognition in the structure-forming step and which are reconfigured in an enzymatic reaction network. This nonequilibrium systems chemistry approach to pathway complexity provides new conceptual insights into fuel-driven automatons and autonomous materials design.