For The Commander to have a relationship with any of his subordinates could set a bad example. Kurosawa would be a bad fit being as she is a Thunderfist and her life is always in danger, also she sounds too experienced and jaded to take a relationship seriously. Tanaka would make a better wife/girlfriend being as she and the commander are close to the same age and her job keeps her out of danger. Sally would also make a good wife (after she grows up) since she seems to have a thing for the commander. Since the Aliens are no longer experimenting on her she should start ageing again, so in 6 years or so she would be old enough to romance. Amata is a good possibility too, shes shown she can make tough decisions and is willing to put the welfare of the Vault before what she wants. Bringing Vault 101 into the TSC could get the people there to stop being mean to the commander, freeing Amata to romance whom she wants. Politically Sarah Lyons is the best choice, it would solidify the relationship between the TSC and Lyons BOS. But Sarah is also a hard charging ground commander who is used to being in charge, this could lead to friction between her and The Commander.