You can indeed field two ashigarus or two shin agents, and 2 boepripacy for example.
With the shogunate I like better fielding 1 of each (shin with stamina, ashigaru with combat) and in turn 1 I give the automatic weapon and the extra ammo to the Shin agent so with the art of surprise she rolls 7 dice (she gives back the first aid kit and the pistol). Then I spend grenade and first aid kit with the ashigaru and sacrifice him so he can come back as reinforcement fully equipped again. (Obviouslly you need someone equipped with call in the troops to pull this off if playing for 2 cps).
With the Matriarchy my preferred strategy is fo field 2 zazizag with command pack with zorka (stamina) and Irina (stamina) and use the fire grenades. That way I can deny one part of the board (a big part depending on the map and where you fire it, look for tri colored circles) during 6 turns to the enemy (2 grenades in a row) and walk freely through it with 3 of my characters (zazizags are inmune to fire and Zorka rolling 5 dice with successes on 2+ also qualifies as inmune). Not an option if playing the union with Ramirez by the way, he can put out fires with his bonus pack. Voivodes are for Oksana…
My preferred team with the reich has Hoss (Command), Eva (combat and elizabeth bathory), and 2 stosstruppen (command) I call this setup the Reichdoktor abuse. Stosstruppens heal themselves with each wound they make so no pain from reichdoktor and as soon as eva rolls a 0 the opponent is rolling 2 less dice, so with reichdoktor it is 90% an insta kill and ista full health for eva. With 3 characters freely reichdorktor-able I (ab)use reichdoktor once every turn.
With union… since Edison, it is all about three troopers in 2 cp games and 4 troopers in 3 cp games, I dont have 4 of the same so I do 2 and 2.