well the triarii I used can also form a phalanx but I barely had to use them I used backed my triarii and hastati up with them. most of the hoplites were hoplitai iphikrates or something like that .
wel I used skirmishers but they all threw their javelins against the greek peltestai.
wich were beaten by my hastati.
I just used the roman tactics from DA's guide. first send in the hastati then the principes and then the triarii. ofcourse I gave support to the weak areas and such.

ofcouirse note that the stats I used aren't the latest stats. And that even the latest stats are still a WIP.