The "Fred thread": the Argead Macedonian Army

[Paralus]

Firstly, how much range of motion of the slung-forward shield would have been necessary with any orientation of grips, porpakes, or straps when just using the sarissa? Not much, I think.

Absolutely. Up, down with and forward, back with a sarisa. The telamon, baldric or whatever supported the shield and the wrist strap / antilabe "drew" the shield. The length of the strap will have been something of a personal matter I imagine.

Equipping a Macedonian phalanx was always going to be expensive in the Hellenistic period, between the manpower, the armament, and the training, which is why so many minor states never fielded one. If, however, some skimping could be made in order to cut back on the initial cost of creating one, then the king would be all the more likely to get his reforms off the ground (and the importance of expediency in such matters was clear from the failure of Agis IV's reforms). Cleomenes III did not have ample resources, which is one of the reasons why it was felt that this reform was so necessary (in order to boost Sparta's military strength without the king having to resort to campaigning to muster money to hire mercenaries), and it's not like bronze could have easily been reworked. That all required time, money, and dozens, if not hundreds, of skilled smiths. It would have been much easier simply to pop off the porpakes (or keep them, but I find that less likely), and modify the shields by attaching simple telamones and lengthened antilabae. After all, leather was cheap and plentiful.

Uniformity is all: the pikes definitely will have been made and to a "template". If it were important that the pikes were uniform the shields will have been - in the ideal world - as well. Hence I see no reason why Kleomenes - already paying for mercenaries and in a hurry - would not have made use of those shields available. There is little, that I'm aware of, to suggest that conservative Sparta had overthrown the hoplite mentality and it is therefore likely that those available shields will have been aspides. I'd think this even more a necessity for the 2,000 helots to whom he sold citizenship and membership of the phalanx.