First some character specifics.
Martin Tiberius Kholran
Age: 25
Race: Imperial, with Nord blood on his mother's side.
Class: Warrior trained in the Akaviri way of the blade.
Job: Mercenary
Short Backstory:
Martin (named after the last Septin and savior of the Third era) survived the murder of his family through the intervention of his Blade Grandfather's friend and fellow Blade, a Redguard named Ruslen. Ruslen took Martin to Stros M'kai, where he trained him in the Akaviri way of fighting. When he came of age Martin sold his skills as a mercenary, and fought in the vanguard that forced the Dominion to abandon their campaign in Hammerfell, and sign the Second Treaty of Stros M'kai. Martin has turned his sights towards Skyrim, the homeland of his mother, where he has been told that Thalmor activity is strong, and most likley prolonging the civil war with the intent of further damaging the Empire, militarily and politically.
So my primary question is this, out of these three choices who is the best fit for a companion? Borgakh the Steel Heart, Lydia, or Brelyna Maryon. Also feel free to provide role play sugesstions for this character.
Cheers