Roman armies from the Late Antiquity to Early Middle ages are perhaps one of the most powerful and most diverse of its era, but also very much reliant on its commanders ability to use them. So their military units would be micro intensive and also have multiple abilities.
- Cataphracs: Knight replacement. Very heavy cavalry equipped with a bow and a lance , has a special “Wedge” formation ability, but also a lot slower than a regular knight and very expensive to field.
- “Wedge Formation”, slows your Cataphracts down to a crawl before unleashing a devastating
charge to their intended targets with area of effect damage, very effective against infantry but also make your Cataphracts take another extra damage from spearman after the charge ended.
- Hunnic Tactics (Stable Upgrade): Light Cavalry gains a bow but also increased in cost, Cataphracts range attack also increased.
- Skutatoi (Spearman Upgrade): Spearman unit line would be equipped with shields, gains “Te tsudo” and “Shield Wall” ability
- “Te tsudo” Spearman would raise their shields above their heads, severely decrease incoming missile attack, but won’t be able to move
- Shield Wall: Spearman would raise their shields in front of them to resist enemy calvalry charges also slows them down.
- Verutum (Man at Arms upgrade): Man at Arms gains a charging ability to throw javelin before charging on the enemy.
- Magister Militum as scout unit
The Byzantine Empire Speculation - #6 by Alexios732
This is just my take on your unit lists feel free to comment on it.
Sources: Elite and Levy Units of the Eastern Roman Army, by Kings & Generals; Strategikon - Army Manual of the Eastern Roman Empire, by Kings & Generals; East Roman army - Wikipedia; Byzantine army - Wikipedia