Unit formations

Just a quick 1, whilst making my move to dominate the german forces i was flickin thru which is the best infantry to mix with what ect. My standard armies consist of 1 general (sometimes a younger general to co-exist and learn traits along the way) 8 principies for the main frount line 4 triarii to protect the flanks and lauch attacks from the enemies rear, 2 units of cavalry, sometimes an extra 2 units of campanion cav when they have lots of experience they can be quite deadly and 3 - 4 archers. depending where im fighting and who against depends on which formations i use but this is the genral picture.

I was just looking at the elite heavy infantry of the italic allies and it says next to their weapon type that it is light? Weird considering the name stats heavy infantry. And also triarii it says a light weapon is this right?

Im not looking for a realistic infantry formation i just find this to be the best ne 1 got better ?

Against Sweboz, or any other barbarian faction around there, I'd use a whole bunch of missile troops along with the regular checkerboard type formation that I like to use with the Romans. The checkerboard formation seems to work really well against most enemies I've come across, mainly Hoplites and Pikemen, or anything else Carthage can throw at you, but I bet it'd work just as well up north.

"Weapon weight class" is for all intents and purposes utterly irrelevant to anything and everything. Ignore it.

My roman armies ussually consist of, 2 hastati, 2 principes, 2 Triarii, 2 velites, 2 pedites extraordinarii, 2 samnite spearmen or something similar, 1 unit of roman knights, 1 unit of allied cavalry.

I can increase the infantry and cavalry components when necessary.

yes but doing that romanus ur not gaining the best advantage of been able to pump out masses of infantry and retrain them easy, keeping to the same basic infantry emans you can have huge supply lines and retraining facilities easy to access, also i find the roman skirmish infantry to be an absolute waste of time, because ur frount line of principies will do exactly the same thing when the enemy nears, atkeast after ur principies have thrown their javelin they can actually do some fighting ur skirmishes r useless. Unless u wanna use them to cut down fleeing foes, but campanion cav r best for that and they are basically skirmishes on horses so they are my choice over skirmish infantry :s

Well, i would say that my best tactic with the romans is:
6xhastati
6xprinceps
5xtriarii
1xfm
2xroman cavalry(dont remember the name) or equites extraordinari
triarii on front, right wing with princeps, left wing with hastati and on the back the cavalry.
i put the wings oblicuous, so, they cant flank me, and then i start pushing them with hastati and princeps and make them too close, so i finish them with my cavalry
And if i'm overwhelmed by the number of enemies i usually use the famous triangle formation with the triarii in the front line or where the fight would be more complicated, a couple of hastati and princeps closing the triangle and some troops inside so they can push when necessary,with my cavalry outside, ready for smashing the enemy backs or hunt down the missile troops :)