Congratulations on your new hives. Why not stick with mediums. I originally built deeps and shallow boxes and have been slowly removing the remaining deeps and cutting them down to mediums, boxes and frames. It is really nice to bee able to switch frames up and down in a hive, especially for checker boarding. You can also leave mediums in a deep box and they will build below the frames. I put mediums frames in a deep nuc and then cut the brood comb that is below the frame and place it in a medium frame and make a 8-10 frame medium hive.