I've been planning similar for the shields. There are currently 2's, 4's, and 5's. I already gave the Iberians at 3 since the caetra deserves that. Some of the smallest peltast/slinger shields probably deserve only a 2 as given.
The early principes/hastati probably deserve their 5 shields, although the shield shown in the game is probably a bit better than what they had at the time. A 6 or more likely a 7 for the later legionary scutum seems right.
You will find the chosen swordsman getting a 5 for their small round shield...that is clearly wrong. Their description doesn't match their graphics, but since I'm $3,000 short of the software needed to change this, I am going to switch them to a 3 instead of a 5. Regular swordsman are getting a 5 from a mid size round shield. I'm probably going to give them a 4.
The hoplon aspis I will probably leave at a 5 although I might give the metal covered ones a 6.
I am giving the mid size round cav shields a 4 and the smaller ones a 3.
Large ovals = 5, mid size ovals = 4.
I agree that wicker shields should not exceed 4 for the largest.
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