The situation with the ancient Greek Phalanx is ore complicated than the OP seems to think. the Phalanx isn't "just" a tactical formation, but also encapsulates the social order of Classical Greece as well. One might wonder why the Greeks evolved such a formation given the argumentative and relatively individualistic (for the time) culture of classical Greece.
Members of the Phalanx were mostly middle class farmers, with some townspeople and tradesmen thrown into the mix. The arms and equipment were about equivalent to buying a new car in Purchasing Power Parity terms, firmly excluding the poor, while horses were rare and far more expensive in ancient Greece, so the domain of the aristocracy. A wall of fully equipped farmers with bronze helmets, 3' diameter shields locked together and protected by bronze breastplates, greaves and other metal armour was essentially immune to the weapons that the poor could bring to battle (stones, javelins etc.) as well as the thrown javelins of the aristocratic cavalry (stirrup mounted shock cavalry was 1000 years in the future).
Standing together as equals on the battlefield and unable to be defeated or driven off by the rich or the poor, Greek farmers could also stand together as equals in the Agora and eventually in the Ekklasia to create and enforce the rules and laws of their communities.
The Classical Phalanx was also able to co-opt the poor and aristocrats as part of the formation; for example cavalry tended to operate to protect the flanks, while "Peltasts" drawn from the ranks of the poor attempted to harry the flanks or disorganize the enemy Phalanx when it was on the move, and thus more vulnerable to being crushed by an organized advance by the opposing Phalanx.
Peltast
The Phalanx was also capable of some limited tactical manouevre, although only the Spartans, who drilled full time, were capable of really exploiting the possibilities of a Phalanx. The Theban Boeotarch Epaminondas also introduced very innovative tactics that turned the traditional Phalanx from a solid line of troops arrayed 8 deep into an articulated formation, defeating the Spartans using these tactics at the Battle of Leuctra (371 BC), and then invading Laconia and overthrowing Spartan rule there as well, before dying at the Battle of Mantinea (362 BC).
"Special Forces" also existed in various Greek polities during the period. The Spartans had a 300 man elite corps who served as the King's guard and stood at the right of the line to anchor the Spartan Phalanx and prevent it from drifting to the right, while the Thebans created the "Sacred Band", a 300 man strong striking force made of paired homosexual lovers. The Sacred Band detached itself from the main body of the Theban force during the Battle of Leuctra and struck the Spartan flank, preventing them from carrying out some sort of countermarch or manouevre while the main body of the Thebans bore down on them.
In terms of the concept of "Mission Command", independent commanders generally could only receive general instructions from their Ekklasia, and the various elements of a Greek Army would be unable to communicate with each other during the encounter, so the local Stratigoi would need to be able to assess the situation and take whatever action they felt was appropriate. The charge of the "Sacred Band", for example, is said to have been triggered by Pelopidas observing the Spartans beginning to countermarch, rather than any sort of command given by Epaminondas during the actual battle.
So although the idea of "Mission Command" may not have been formalized in the manner we think of it today, the basic elements of the concept did exist.