A bug or and should be? (Total War: Rome 2)

I decided to play Рим2 a few years later. I started playing in BC. From the very beginning of the game hurts only one. Or rather one. Squad. Prediki! All the armies of the enemy have 4-5+ units Persikov, and the rest is groups of homeless people, peasants or Eastern spearmen. So, homeless people, even peasants, can easily hold my heavy infantry and spearmen, and predici carry my entire army in the trash. My archers and predici useless, they seem to do no damage, by the time my 2-3 squad will only kill one squad of Prasolov, use up all ammo, my infantry is already full of lies. What their armies predici the enemy did not seem to fall. Not yet circulated the cavalry with all such armies had to fight the auto combat, hate big losses but in manual battle it is generally a lose. After the battle statistics of murders in the 4-5 squad of 300+ on the unit. Now the situation is such: we studied all the technology, and staffed with cavalry and artillery. Grade 5-7 fighters, weapons and armor level 3. Win without problems all the battles but they are ugly and continue to mow for a significant portion of my army. Campaign difficulty: very difficult. The difficulty of the battle is very difficult. Ie not even a legend. As it should be? Homeless people without armor, protection, attack, easy to hold "elite fighters", and the other bums put my entire army? The game client is new, but the Files in "my documents" even 5 years ago, then doing any "editing" in the game files, whether documents lie something where I could screw that up?