You could also make the Scipio Africanus version of Triplex Acies. With lanes rather than a checkerboard.

You could create a phalanx formation of en enchelon one way or the other where each phalanx unit protects the next by virtue of its pikes/spears. That would grant the phalanx armies a great versatility when facing melee strong enemies as it would present their cavalry with a great opening. If the enemy attacks the line head on they will end up in an echelon themselves and the the cavalry will easily sweep them from the side that is farthest back (from the phalanx position). Any melee troops should be postitione right behind the phalanx units. This formation was used at Issus by Alexander.