Silicon photonics routers and band-pass filters employing ring resonators are usually constrained by a trade-off between quality factors and insertion loss, which is even more pronounced in compact designs. Device real estate is another factor to be considered for compactness and cost reduction. We propose an approach to simultaneously reduce insertion losses and increase the quality factor in such devices, while minimizing footprint. This approach consists in replacing the standard SiO2 top cladding of Si devices by erbium-doped Al2O3 films with a single post-processing step. Experimental results confirm the effectiveness of the method, where 1 dB output power increase is observed for a single ring device, in addition to an increase of 5% in the Q factor. In some cases of structures comprised of multiple coupled resonators, i.e., photonic molecules, the observed value of power increase is as high as 2.6 dB, with a Q factor increase of 25% and loss reduction of 3 dB.