Victrix boxes have same parts for bodies, arms, shields and spears, the only differences between them are heads, instruments for musicians and cloaks. Victrix spartans have chlamys cloaks, double greek flute and mostly pilos helmets. All of the heads have distinct spartan hairstyles. Theban hoplites have beotian helmets and trumpet held in one hand. Athenians have more hellenistic style helmets, normal cloak and trumpet held in both hands. Mercenaries have mix, with mostly hellenistic style helmets. That distincion is somewhat artificial -it would be much more proper to mix the helmets, maybe only spartans could be more uniformed and their hairstyles would have to be corrected before using the heads in hoplite armies other than Lacedaemonians. The beotian helmets for example were not in use only in beotia, probably there were not even more popular there than in any other part of greek world. Their use was more common in cavalry as there were not as limiting vision and hearing as other styles of helmets. To answer Your question -all of those boxes could be used to make units for one army, the best way to do that would be mixing them rather than making separate different units.
As for colours -the hoplites were citizen force and there was none uniformity, or perhaps even no colours distinct for different polis. Warriors usually bought equipement themselves and colours and designs would vary. Spartans were exception -they wore red cloaks and used lambda symbol on their shields.
If You want Iberians in Your force fighting alongside greeks You can model Your soldiers as hoplites from Syracuse -tyrants from that Sicilian polis employed a lot of mercenaries and iberian cavalry could likely fit in Syracusan army, alongside other exotic warriors: gauls, italians, etruscans.