through my four years of RTW experience and my few months of online play ive learned that the Roman infantry simply cannot be bested in frontal combat. And after a few long nights of R&D with Alex, we've built a solid Roman Army. For anyone wishing to go Roman when online, I reccomend that you use it because in the right hands, its pretty much the DEATH STAR of the Ancient world. (I know yall have seen ALex and I bring this to the fight many times so i know its nothing totally new)
5 Urban Cohorts [Gold/Gold]
3 Praetorian Cavalry [Gold/Gold]
2 Triarii [Gold/Gold]
4 Roman Archers [Gold/Gold] or 2 Auxilia Archers [Gold/nothing]
The set up is pretty straightforward. Line up the Urbans 3-4 shields deep (depending on the size setting i like small or normal), put on triarii a little bit behind the right most cohort and do the same on the other side. Line up the Praetorians behind the triarii and sitck the archers up front. Its always best to put all the infantry on guard formation especially the triarii.
I find that wide flanking manuevars do not work well with three praetorians if you're fighting someone with good cav. Just draw in the enemy cavalry or better yet, wait for them to flank you. The triarii can easily hold a line and have incredible staying power and you can use them against chariots as well and your guaranteed a few routs.