Generally, Byzantine are represent most of infantry, particularly roman legionnaries, standard bearer, centurion and later Celtic and Gallic warrior. They also have support combat such as ranged pierce Pilum and heavy cavalry like Cataphract. They also has excellent defense, decent navy and siege engine. In Roman Campaign these troops display specialized trait:
Roman legionnaries has ￼decent statistic about attack, hitpoints, and armor. They have special ability called 'Pilum attack'. This ability allow them to throw their javelin at their target. This only happen at enemy and not ally. They are the backbone of Roman Army. They are rather cheap, cost 35 both of food and iron.
Standard bearer has a morale ￼influence nearby. They have high hitpoints and decent armor but low attack.
They are ideally geared for combat support due to their morale influence nearby unit. They are moderate expensive, cost 50 both of food and iron.
Centurion has a powerful attack and high hitpoints. They has special ability called 'Centurion Battlecry'. This ability work to similar to hero battlecry, demoralize enemy unit so they can take more damage. They are the most expensive infantry unit, cost 70 both of food and iron.
Gallic Warrior can walk through forest. They have high hitpoints and powerful armor, often the cost are they, along with the Legionnaries, Standard Bearer, and Centurions, have relatively slow speed and they have low damage. They cost 35 both of food and iron.
Celtic warrior can walk through forest. They have decent damage, high hitpoints, and fast speed( the fastest melee infantry)but low armor. They are cost 35 both of food and iron.
Pilum ia a ranged pierce unit. They are suited for backline support, use their range to deal damage at long range while support the frontliners. They cost 30 gold and 40 wood.
Cataphract is a cavalry unit, has decent attack, high hitpoints, and fast speed,but take 2 pop cap for one unit. They are most effective to reconnaissance mission, flanking and encircle manouvre. They are expensive, cost 60 both of food and gold.
For that points, it better for you to use triangle set.
Infantry act as frontliners, pilum deal damage at range, while cataphract flanking and encircle the enemy.