I think the Phalanx is almost useless, outside of its role as anti-mounted. Which regular Spearmen do just fine. Axemen are too strong when fighting them.
Giving Phalanxes a bonus vs melee is the only real option to extend their lifespans, so they can fight axemen. Maybe this would work.
Phalanx- 5 strength
10% vs melee
100% vs mounted
With this setup, they would easily be able to fight, but not overwhelm, axemen. It would basically be a 7.5 str to 5.5 str battle.
But, Alexander is Agg, so it would be 7.5 to 6.05 str, but with a shock promotion the phalanx would stand a chance. Of course, axemen with shock would own them...
I dunno, my plan isn't that good for fixing them. Does anyone have a good idea on how to? The problem is axemen come too close after spearmen,