It really depands if you are planning to use hardcore or allow save/load and how open are you with abusing save/load.
If you allow yourself save/load abuse, you can use few gamechanging tricks:
0. You really need StR/AGI/Leadership in the beginning (Plus horseriding 2, of course).
1. In the beginning of the game, to make fast cash: Joining large battles on the side of large armies vs other large armies. Emprison Lords/Dukes from that fight, let them go for money. While you spoil relations this way, money are more important, relations can be fixed. You also can identify some honorable lords, or lords which generate nice armies, and let them go free increasing relations with them.
Why I think it's exploit. Because you can join with really small forces to a fight and still get your share of prisoners (or all of them, I don't remember mechanics already). It can be abused easily. It's really the fastest way to get all companions you want.
2. Rushing Noldor quest.
Part a) build relations withj Noldor - just rush east, find Nolodr armies, follow them, and join battles between them and other - join against Noldor, get loot, get prisoners or just on their side to get relations if you can't win against.
Part b) marauding army. You can do it really, really fast if abuse load/save. Just get a qualis gem from Rane hodden chest, then get a (guildmaster?) quest related to find and kill some bandits, then you can play a game putting qualis gem on the stake. You can use this 3 times. Each time just load/save until : you want and your gem is still in your inventory AND you got Noldor troops. So you get 2 sets of Noldors in your army without Qualis, and third time - you can't win without loosing the gem, so 3d time yo get Noldors in exchange of a gem. This army is capable to kill that maraiding Jatu Army from the quest. Kill it. It can be killed WITHOUT loosing ANY NOLDORS, you just need to route/attack several times.
Finishing that quest you get to Noldor castle tournaments. I usually join second possible tournament. Again, it's a load/save abusing, as winning there is qute hard, especially early. Win, and accept victory either if you want what you get. Usually it's qualis gem, but you can accept some superexpencive armor, which, while you can't use immediately, you will need later. I would also consider VERY good horse. NEVER take Noldor bow or swords as a prize.
3. With Noldor army from quest you can setup your order really fast, so time will start working for you (it takes A LOT of time to get your knights equipped as you want).
4. Good to defeat unique powerful Noldor lords. You can do it for gems, several times, or get secret knowledge (you need that), or Unique weapon (I only use Bow of one of them. The sword is not that unique).
5. What you really need now is "The Three Seers" army. DON'T MISS THE MOMENT of their appearance! Don't let some Lord's army to kill that army. Take as first your castle something closer to the route of The Three Seers - the best one is Avendor. And you need to have own castle before you start doing what I say here.
YOU DON"T NEED to kill that army. And you can't let happen being defeated by any prize! They spawn small armies, don't miss them! Learn when they spawn (it happens each specific day of month or something like that - don't remember). Hunt for that armies with blunt weapons only. Follow the advice from here related to not allow your prisoners flee first night (find it in forums).
6. Imprisoned Seer Favorites and Seer Initiates from "The Three Seers" army you train to Doomguides. These Doomguides are crazy and you need as many of them as possible. You can also use tactical autocombat with these small 3 seers armies to get Doom Maces , which is the best weapon in the game - especially if you use that trick, and trading slaves also good.
So resume what we achive:
1. Steady flow of Qualis gems from Noldor castle tournaments, almost every month. You need that Ruby 2h sword as soon as possible as a priority amd always have extragem for the case you get a bow for converting free Strange Bow you get from GOD (read forums when/how you get and how you can loose it), to convert that bow to something like Ruby Bow, which will not be lost anymore.
2. You have early Doomguides. Which are fun and they are nice aesthetically. And Doom Maces,which are less important but still.. Since you got them you can give them to your custom knight order which is a smart move.
3. You have early Noldor equipment on your Knights of your custom order. Especially boots, which are cheap and keep your forgers busy.
So each time I play I just optimize shortest path to these goals.
P.S. One more minor trick to get those Doom Maces (and any other good equipment). Make your custom order - naked, with doom maces, maybe those cool helms with horns. And have good loot skill on yourself or your companion. You custom order eventually will start spawning these guys, which are naked but with superrare staff. Kill them and loot. The skill is needed loot skill , as high as possible, for that. And never equip your custom order with cheap staff, as this option will be closed (you will always get some crap loot
instead of maces)
P.P.S. Another, not a trick, more an advice - give Rubi/other good weapon to lower level companions you want to grow. It is critical.
Ah, and Engeneering skill and maybe others are not useful for lords which you plan to make your vassals, it's not taken to account when they upgrade their castles and villages as far as I remember. Don't have a full list of skills which are not needed for them.
Any other tricks of the same level of influence on game progress you know?
). Started my conquest by harassing D'Shar, thanks to the negative relation at the beginning, by capturing their lords and ransoming them. After getting some equipment I lead my Noldors to sieges and after a long battle back and forth I get to keep a castle and get in peace with them at day 20 or 30. Then I hunted a unique spawn by baiting the huge 400-500 Noldor army to them and increased my army size with that and the bandit gem. It's day 100 now and I've conquered Marleons, Avendor and 6 castles from the Sarleons and distributed them between 4 companions. Do you guys have any secrets/tips on how to make this process faster? 
