Here is my tactics and insight to the Yoritomo Alliance. Yoritomo's Alliance is swift and brutal, much like the Crab Clan. However, because of their lesser numbers, they must use better tactics to fully reach their potential.

Unit Concepts

One of the most obvious combinations is to have Tsuriuchi leading either veteran ronin archers, or medium infantry with yumi. The medium infantry doesn't have the range and training of the ronin, but cost less if you want a huge swarm of arrows coming down (the more shots fired, the more likely something will hit). Equip Tsuriuchi with the Jade Bow if you can afford it. One of my tactics is to have him lead 15 archers and put them in archer row in a place where they won't have to move a lot. Be sure to have Indirect Fire and The Arrow Knows the Way in your tactical deck.

Ryosei is a good candidate to lead elite ronin guard. Equipped with yari and lead by Ryosei, this unit has both Fast Strike and First Strike. Since she is also a shugenja, use Windborne Speed to give them extra mobility, and Essence of Earth to protect them from missile fire. This unit is hard-hitting and has good moral and heavy armor. Use Windborne Speed to get them in the opponent's face and sit back with a Wall of Spears and Defensive Position to force the enemy to grasp the porcupine so to speak. Use Essence of Earth if their archers get noisy. If you are playing a larger army size (more than 2000 points) substitute the elite ronin guard with Storm Legion.

Yoritomo himself is rather expensive, and his ability to pull together broken units typically finishes them off instead of rallying them. However, he has Double Chi, which makes him good in a duel. Use him if the opponent has another big bruiser such as Hida Kisada or Togashi Yokuni.

Mukami, leading a unit of 8 wasp clan skirmishers is a good unit to have. They embody the idea of the wasp; move and sting, move and sting. Use them to harass any large units, or any unit advancing on Tsuriuchi's unit. Try to keep their initiative after any nearby infantry units on the opponent's side so you can use reactionary fire to hurt them first.

A good (and relatively expendable) unit is to have Ginawa equip Fukushu and lead a unit of 8 or 12 medium infantry or heavier infantry if you want to pay the cost. Use him to Charge into the flank of any enemy unit you are engaged with, or use him to screen Tsuriuchi's unit. Keep a couple Parade Ground Practice and Grim Determination in your tactical deck to make up for this unit's low stats.

Hyobe leading Tortoise Marines is another good infantry combination. The unit will not route as long as Hyobe is honorable and unspent, not to mention they are a solid hard-hitting unit.

Moshi Wakiza is a good personality to attach to either archer unit. She has an innate ranged attack and a good fire ring for using The Fires that Cleanse, and provide extra defense to the archers.

Tactics

As previously stated, Yoritomo's Alliance is brutal and swift like the storms they liken themselves to. A good army for this clan should have two "bruiser" units, such as the elite ronin guard and perhaps Tortoise Marines or other heavy infantry if you can afford the cost. Have Ryosei lead the elite ronin guard as detailed above, and use Kamoto or Hyobe to lead the other unit. Be sure to have Tsuriuchi's unit, (reduce the number of archers if you want a smaller unit) and have Mukami's unit to annoy the mess out of the opponent. Use Ginawa and some medium infantry or some other "shock" unit to try breaking morale with a flank. If you feel the need for extra magic, attach Moshi Wakiza or other shugenja to a unit to avoid the wasted cost of yojimbo.

2000 Point Yoritomo Army

This is a reliable and solid army, having two main units of infantry, and one unit of reserve infantry to use flank the enemy, and two units of archers to wear away at the opponent. The two shugenja provide magical support and extra defense.

Elite Ronin Guard x12	228
Ryosei Exp. Counterspell Windborne Speed Essence of Earth Ancestral Yari of the Shiba	235
Wasp Skirmishers x8	78
Mukami	161
Medium Infantry x8	56
Ginawa (oath of fealty) Fukushu	125
Veteran Ronin Archers x15	255
Tsuriuchi Exp. Jade Bow	233
Moshi Wakiza Exp. (oath of fealty) Isawa's Scroll The Fires that Cleanse Stagnant Air	269
Tortoise Marines x12	192
Hyobe	118
Total	2000

The tactical deck will have a basic "core" of cards you will need to make this army effective. Some of the cards may seem unnecessary, but it's best not to leave anything to chance and fail a critical roll at the wrong moment. The Arrow Knows the Way is a must for Tsuriuchi's unit. With a high amount of arrows hitting, it is possible to take out the leader of a unit in a round or two of missile fire. The Another Time cards are to keep your personalities out of duels since none of them are particularly adept at them. Arcane Fury gives Ryosei's unit an edge for one round, and Rise of the Lesser Clans is very helpful since all personalities except Ginawa are affiliated with Yoritomo.

Another Time x3
Arcane Fury x1
Wall of Spears x1
Defensive Position x2
Grim Determination x3
Parade Ground Practice x3
Charge x2
Countercharge x2
The Arrow Knows the Way x3
Promo - Rise of the Lesser Clans x3
Indirect Fire x3
Bad Karma x1
Superior Tactics x3

I found it appropriate and interesting to give each unit a title to describe its function in the army:

Main Archers (Tsuriuchi) - "Violent Rain"
Backup Archers (Mukami) - "Wasp Swarm"
Yari Infantry (Ryosei) - "Dangerous Winds"
Main Infantry (Hyobe) - "Storm Clouds"
Shock Troopers (Ginawa) - "Lightning Strike"