Electron structure and dynamics in molecular aggregates are central for carrier transport and light-emitting processes. We employ transport models at four different levels, namely, Marcus semiclassical theory of hopping, the Fermi-Golden rule with nuclear tunneling, the time-dependent wavepacket dynamics, and the bandlike model to a class of high mobility organic materials to assess the roles of quantum nuclear tunneling and the electron quantum coherence in the molecular aggregates. It is found that the former is essential while the latter is usually much less important. We further present a recent development in the excited state non-adiabatic decay rate formalism for molecular aggregate. The excitonic effect on the non-radiative decay rate is assessed.