We have RTW building icons that easily could moddified to show cultures like Roman (byzantine) north and south european , Islamic (based on the Persian RTW icons of RTW./BI) etc.
Few samples are these:

The greek trieme ship was relaced by a dromon and also added a city behind it.
Another example:

Nottice the addition of buildings in the back ground.
Finally the black smith

In every culture all is changed is the shield types.

Exepet the photoshop or GIMP experty COMMITMENT is required. We can not have someone that will flee in the middle of the process.
If anyone is interesting please contact me.