And you play as a roman faction or not ??
Yes, of course, the Julii, to be precise. It wouldn´t make much sense trying to test it with a non-roman faction, now would it?

It's a shame that units with a long pike cannot manoeuvre thus, and a real shame that such units only use the sword if equipped with a secondary weapon. Could one give them a spear as a secondary and not give them a primary? Or for that matter, give them a spear for both primary and secondary, each with the same stats?
I´m not quite sure I get what you want. Do you want to make a phalanx unit use its sword? Nothing simpler than that, switch off phalanx mode and give them an order to attack, they´ll use swords automatically. Or do you not want them to use any swords at all? That´s more difficult. You could give them the same stats for both primary and secondary weapons, of course, and change the secondary weapon skeleton in model_battle to a spearman one, but the unit will keep its sword showing (that´s because the sword is part of the .cas models, the "physical" models, so to speak). To make them show to use spears (for the stats it doesn´t matter, you can basically edit them to anything; I´m purely refering to what´s showing on-screen) you´d have to edit the actual cas model, remove the sword and give them a spear as secondary weapon.
Now, things get a bit more complicated when you figure in the phalanx ability. Those pikes the phalanx units carry in the game are not part of their .cas model (though the cas models do have spears on them, just remove the phalanx ability of, say the Hoplites in EDU and you´ll see it), but they come from the phalanx ability, adding that makes them use a seperate weapon model, the Hoplite_pike.cas.