Any antenna with the gain needed to receive the DC signals will be too directional to expect simultaneous reception from edge path signals 50° off the forward beam.
A Winegard HD7698P or a combination of an Antennas Direct XG-91 and a 10 element high-VHF yagi (Y-10713 or YA-1713) would be my choice to chase down the DC signals. A preamp such as the Winegard HDP269 or Antennas Direct CPA-19 would be needed for the weaker signals.
Keep the RCA if it's in good shape, mount it higher, aimed at Baltimore. Add the second antenna or combination if the DC market is worth it to you. If you're not interested in a
HTPC with multiple tuners, an
A/B switch would be practical alternative to a rotator.