I have a few thoughts on Pontos:

First of all, they are the jack of all trades in the almighty EB. They have good heavy infantry (including phalanxes), good heavy cavalry, decent archers, capable skirmishers and a few horse archers. However, they master none of the stuffs mentioned up. You have Chalkaspidai, but they aren't Argyraspides, you have Pontikoi Strategoi, but they aren't Hetairoi and I could continue. So, if someone wants to have a good army with Pontos, then that someone has to know who will be the enemy.

If you fight barbarians:

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They tend to be vulnerable against missiles, however they are very good in melee and have some deadly units with AP weapons. To fight them you will need archers, I prefer the Thureopherontes Toxotai, they are not Cretans (I know, Pontos could use them too as mercs, but seriously, aren't they overused a bit?), but still have the "rain of death" effect. Also, you will need good heavy infantry with swords or axes to hold your line, like Galatikoi Kuarothoroi and Tindanotae (Don't forget, Wild men count as elites). Light or medium infantry with javelins is nice too, but don't overdose yourself with them. The question is, do you need phalanxes against this enemy? Not really, of course a few of them won't hurt, Klerouchoi Phalangitai and maybe a Chalkaspidai will do the job. About cavalry, well heavy one, what you need here. I advice the Skuda Uaezdaettae (elites) or Galatikoi Lavotuxri, they will be able to hammer the barbarian line from rear. Let’s not forget that these units are not cheap, so you have to find the balance how you spend your mnai. With such units you will be able to bring down barbarian armies in 1vs1 fights.


If you fight Romans:

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Cheap and good heavy infantry and decent cavalry with high morale level. One of your two options is to fight them as Hellenes do, use phalanx and heavy cavalry for hammer & anvil and a few flanker infantry. However your units are not as good as the „true” hellens’ so you will have a higher chance to lose the battle if you fight in the „old” fashion. But you can try a similiar to the anti-barbarian tactic too. Your Galatian units are killers, they are better than the legionaries in melee, you can use Thrakioi units also since they are known to be armored-unit-rapers. Don’t forget that your archer units won’t hurt the Romans as much as they did with the barbarians so if I were you I would trade some of them to slingers (Rhodians) or mobile spearmen (going to explain why). A few hillmen (Katpatuka Zanteush) on the flanks won’t hurt either, since they have AP axes and javelins too. Now the cavalry question, you could use the same heavies, buti f the Romans use Extraordinarii cavalry, then it’s a different story, because they will eat you slowly and painfully. That’s why a few mobile spearmen (Hoplitai or Thuerophoroi) and medium cavalry (Lonchophoroi Hippeis) instead of expensive heavy ones will do better in my opinion. If you can protect yourself from their heavy cavalry then your Galatians will overpower the Romani slowly and you will win the battle eventually.


If you fight nomads:

Spoiler Alert, click show to read: 
Hordes of horse archers and armored heavy cavalry. The nomad fighting styles are all agressive ones, they will attack and you can do nothing, because if you move your finger they run away. So you have to sit down and wait till they run out of ammo. How can we counter the extrem losses on our side before that happens? Honestly I don’t really know, I fought only twice against them online. But my advice is that don’t even try to counter their H/As with your owns, waste of mnai and men, don’t use light armored units either (except a few Thureopherontes Toxotai behind your line(s)). Get Pantodapoi Phalangitai and heavy armored spearmen, like Hoplitai and Galatikoi Kuarothoroi (They have spears too) units. In this battle your role is to be defensive; if they ran out of ammo, they will try to outflank and overwhelm you, if your position breaks you lost.


That’s all right now… if something is inaccurate, then correct me.