Basically, BOFFs are valuable for their traits and their abilities. Abilities are trainable, but traits can't be changed. So your goal should be for all of your BOFFs to have nice traits, and to convert other candidates to training manuals for their rarest ability. Note that this might not be their commander-level ability. Most valuable space trait is Superior Romulan Operative. If your character isn't a Romulan, the Rare (Blue) Rom Tac BOFF you can buy at your fleet embassy is your only way to get this trait. Other decent space traits are Pirate (which is hard to get for Feds; hence everyone saying to get a Nausicaan as your Rank 4 Diplomacy BOFF), Leadership (humans), Efficient. I don't know much about ground traits. (edit: s/skill/ability/g) (r/sto)

In reply to a post on r/sto:

Basically, BOFFs are valuable for their traits and their abilities. Abilities are trainable, but traits can't be changed. So your goal should be for all of your BOFFs to have nice traits, and to convert other candidates to training manuals for their rarest ability. Note that this might not be their commander-level ability.

Most valuable space trait is Superior Romulan Operative. If your character isn't a Romulan, the Rare (Blue) Rom Tac BOFF you can buy at your fleet embassy is your only way to get this trait.

Other decent space traits are Pirate (which is hard to get for Feds; hence everyone saying to get a Nausicaan as your Rank 4 Diplomacy BOFF), Leadership (humans), Efficient.

I don't know much about ground traits.

(edit: s/skill/ability/g)