Romans have the best infantry troops in the game. They do two things well, most of the time.
Legions attack well, and defend well against horses
Praets provide excellent standing defence against enemy infantry. And given that infantry is much cheaper to produce than horses, they are the most important defender in the game.
Imperians raid well, and are the best attacking troop in the game.
If I was a small roman, the only horses I would have would be scouts, and an EI hero. The hero should be fast, so it can zap between villages.
One problem with the way most romans tend to play is that they think praets = defence. This is partly true: praets = INFANTRY defence. When I scout a village and see 500 preats, I attack with horses, and they are toast. Check it out on the combat simulator. Attack 500 preats with 1000 imperians, then attack 500 preats with 1000 tt's. Watch for the difference.
So, defending romans need to mix preats and legions, in a 2:1 to 3:1 ratio. The preats defend against infantry, the legions against horses.
The ideal scenario is to produce preats from one or two villages only, and legions from one or two villages only. Then, presto!! a bit of reinforcing and things are sorted. Reinforce some preats into the legion producing villages and vice versa, and you are there...
Then, produce imperians from an entirely different village altogether.
Feedback is welcome.
p.s Made by Mr_Burns