What I find problematic with the big amount of lords and parties is, that they stick with their clans and kings, even after they have been soundly defeated, and all they do is try raid villages.
When these lords are released or escape from captivity, they all get a new party for free. It's a rubbish party with a lot of recruits. Completely harmless against player (or a kingdom which is still victorious) in a battle.
You can find couple of dozen of these defeated parties swarming around someplaces. The A.I. is so stupid, it often happens a vassal of the player goes and attacks one of these harmless parties, and a dozen (or more) of these parties join the same fight. As the battle is fought only by numbers on the campaign map, the huge number of these harmless newbie parties can still defeat a strong NPC-party, even if they had no hope in a real battlemap fought battle. This continues endlessly, as them defeated parties always start with new free parties, and they won't abandon their clan or kingdom.
In my game there's even several non-kingdom factions brought by mods. Their parties are absolute rubbish, as they've lost a battle some time. They keep declaring wars against me all the time, but it is completely meaningless.
I voted for bigger maps and more lords, but the system of them getting free parties and sticking with their leaders needs to change. I might solve this by breaking these clans, and adding these lords into towns and villages. Make them merchants, gang leaders, farmers, what ever. And also seeking to join other factions or starting their own. Loyalty is too high in this game.
With the stupid tribute rules I won't ever make peace with kingdoms I'm at war with. I don't loot villages, they do, and as a result they still demand tributes when they are soundly defeated and lost all their towns and villages: no military power left. After I've defeated 2-3 of their biggest armies, their troops start to be rubbish, and they can't recover from that.
In my current game there's only two kingdoms left besides mine. The other has half a dozen towns, the other only 2 castles. All the defeated kingdoms still are around, they declare wars, and their troops are absolute rubbish.
If I talk some of these defeated parties, their reply is always that I need to find their clan leader to talk about deserting their kingdom. They will not desert their clan leaders. And as I don't have time to ride looking for these clan leaders, I never bother hire existing clans. I just create new clans by giving fiefs for my companions. MUCH easier and faster.
I think the game needs more kingdoms, so kingdoms have time to rebuild.
And it needs small kingdoms that players who start the game, can have easier adversories and defeated kingdoms could rise again fighting someone who they have chances against. (Yeah I know there are rebelling towns, sometimes a few: that is good).
And it needs big kingdoms who don't try to declare wars against all the small kingdoms first.
And it needs alliances, so that even small kingdoms can find safety. Of course it needs politics so this could happen.
And it really, really needs to get rid of the stupid different culture governor - different culture town penalty. That artificial rule to stop kingdoms from expanding (and guarantee the player wins every campaign) is the biggest nerf. Yeah I know it exists because it can take a long time to rise from farm boy/girl to a prince/princess, and they obviously want the campaign map still exist with different kingdoms. But it could be done otherwise than nerfing the expansion of all kingdoms. And if you spend decades being employed by another kingdom, is it so wrong that one kingdom (other than an Empire faction) could rise in the hegemony in the meanwhile?
If you have a campaign map with only a few kingdoms, it would be just about one war against each. And the defeated have no chance to rebuild. A very short campaign.
In a big map you might have some use for strategic planning even. Which front should you bring your party/army? Which garrisons need to be strengthened?
Unfortunately in current state of the game, there is little chance you could strengthen any border garrisons. NPC-lords don't do it, and when there are continuously wars, you can either transport troops between garrisons (boring), or go have fun and fight battles, but you don't have time for both. Especially in the end game you have not a single day of peace. Meaningful politics, both for declaring wars and trying to get time to rebuild, get allies, would be needed into the game.