I made this diagram back in 0.81 days. Put the last phalanx from reserve to the front would be my opinion today, but the rest I'd do exactly this way also today.



On the flanks in the front line position Thureophoroi. The reserve center should be built of elite heavies like Hypaspistai, Galatian Heavies etc. On the outer position light flankers preferably with AP attribute, like Agrianians. Before the front group Thraikioi Peltastai, they double as skirmishers and AP infantry. As for ranged infantry I recommend Syrian Archers, or Bosphorian Archers. Cavalry: FM and another squadron Hetairoi, two squadrons Thessalikoi, on the flanks Thraikioi Prodromoi. This is a superb army that cuts Romaioi to pieces.

In battle, just hold your ground until they come, or avance at a slow, controlled speed, pikes up. If you have to attack their line, ram them with the pikes down, then halt them once they made contact via Backspace. Put basically every unit into guard mode except the cavalry. Normally a unit of the enemy tries to flank you and lines up in a 90° angle to your flank guard. Rearrange your Flankguard Thureophoroi in a 45° angle to your pikes then. Use your Reserve line for flanking (guard mode off then). Use your equestric supremacy to annihilate the enemy horse, than finish them off with a charge in the back.

Give them time to group, don't run at them like mad! Your army is not build for that, and it also screws up totally any battle experience due to the intellectual deficits of the AI. Slowly, controlled and micromanaging instead.