> If you do want to keep the pilum universal, I suggest that it be
> available only the first time the unit engages in combat: sure, they
> carried two, but I suspect they'd have thrown both (particularly as they
> were of distinctly different size) in the initial charge, or dropped them
> when going hand-to-hand, as carrying a throwing spear in your left hand
> makes it really hard to use your shield effectively.
>
That sounds like a reasonable alteration. I suppose, as an alternative to
the Pilium/missile attack, there could be a one time benifit as follows:

+2 to melee rating the first time the unit is engaged in any given battle,
and cannot be charged in that engagement.
That actually may be a more elegant way of administering it, with
(slightly) less bookeeping. We'll just ignore the Pilium's affect on
shields and the like.