This mod was not meant for the casual gamer. It was meant to be very challenging and requiring more advanced tactics. You can though change party sizes in the code if you want to boost yours and many other changes to help even the odds.

There are other ways to get your party size up though. If you have companions like Selmy who are high in charisma, that gives you a party boost. I have about 1500 in Charisma, a one castle, and 5 companions and able to have 350 men. Thats plenty for seiges and larger battles. A little strategy is necessary here bub.

It's useful to have vassals in your Kingdom, be they Lords or former companions. They police, protect and administer your lands and they also bring huge battalions to battles - thus tipping the balance of forces in your favor.

A very easy way to steal the vassals of the other Kingdoms (in other words, their power base), through cheating, is to open the "Reports" tab and cause the lords of some faction to fall out with their respective liege. I also recomend increasing your Right to Rule. Then simply contact those lords when they're alone for a private conversation and ask them to support you in your claim for the Throne. If you have high enough Right to Rule, the first argument will suffice to sway the lord - the one that says you should be King due to ancient customs. Because the lord now hates his original liege, he will be very willing to change his loyalties even if he's the "upstanding" and honourable type.

There is a random element amongst the variables for the "test" of persuasion and loyalty change. Therefore, even if the lord refuses your proposal at first, you can just repeat everything again and again until he accepts. To put the odds in your favor, make them devoted to you, bring some soldiers along, or be near your other loyal vassals when you invite the lord for a private conversation. I remind you that if your target lord is not alone, he will decline your invitation for a PRIVATE conversation.

As you may have realized, it's necessary to have the Cheat Menu active to implement this strategy.

This way, you can unify the land under your banner and command endless legions of loyal minions to crush your enemies, see them driven before you, and hear the lamentations of their women.

Sorry for any English mistake on my part.

You can create up to 4 if i remember correctly mercenary parties if you use Mercenary Captains, put as much troops as you can and you can have huge armies this way, also there are wandering companies that can be hired for gold, also its a good idea to weaken a faction by capturing its lords.

I was never able to finish one of my campaigns due to updates :D But in recent game, I was just wandering arround alone with no army, building up enterprises, winning tournaments and fighting evertyhing not too big and who has no bow or crossbow and I was able to get like 1.6k renown or smth like that (~50 renown per battle won, I even took down Robber/exiled knights on my own) and with this much renown only (havent put a single point in charisma) I was able to get my party size to ~270. So, its not worth adding a single point in charisma, you just need some alone time :D

if you want an easy GOT mod try a clash of kings

My tactics is to have atleast 75k per week. Unless you cheat money.
Jump to Qohor
Buy unsullied then stash them in your troop quarters.
Do this every week in between of what you do.

Not fast, but stable and very CHEAP. 0 Wages :)

Easiest way to siege with lots of troops is give your Vassal/s all the unsullied gathered. Not good at chasing enemies at fields but very good for sieging.

If you don't want them having the unsullied, either really play hard and get 10 leadership with you and all your companions + thousands of renown. or cheat your renown. :P

Get alot of heroes and give them alot of leadership, these heroes I reccomend you leave rather untouched in battle because that should be there only purpose