These are the heroes of fate/zero and fate/stay night primary ones I have selected are Gilgamesh, King Arthur or Artoria, Cu Chulainn, and Medusa.
Gil: because starting point of heroes
Astoria: because of her unfair raising and her never truly being happy
Cu Chulainn because of Scáthach to increase spear proficiency and runes also possible wifu.
Medusa: because of unfair past but won't change anything until the end of her story.
Fate/zero
Gilgamesh- archer class 1800 D.C
Alexander the Great-rider class 356 D.C
Diarmuid Ua Duibhne - Lancer-class 2th-4th century
King Arthur Pendragon- saber class 5th-6th century
Sir Lancelot du Lac- beserker class 5th-6th cenury
Hassan-e Sabbāh - assassin class 11th century
Gilles de Rais- Caster- class 1420
Fate/Stay Night
King Arthur Pendragon- saber class 5th-6th century
Cu Chulainn - lancer class 9th century
Medea- Caster class thirteenth century
Heracles - Beserk class 1276
Sasaki Koujirou- assassin class 1612
Medusa- Rider class 1808