Boudicca has a bronze girl-chested armor which is both fantasy and inaccurate:
Caratacos has the weird belt from its concept art, which is conan the barbarian -like stuff:
http://images.gamedev.net/columns/spotlight/0AD/big02.jpg
http://images.gamedev.net/columns/spotlight/0AD/big02.jpg
Cunobelin is less problematic but he has weird leather straps (purely decorative) over the body and with buckles (belt buckles are actually something the Romans popularized, the Celts used belt hooks and rings), there is also a Roman fibula on the shoulder (the penannular fibula appeared during the Roman empire) and the wooden scabbard that should be in metal and on the other side:
Vercingetorix still has a round shield (which isn't accurate), the scabbard on the wrong side and a weird belt:
Viridomarus uses the Battersea shield (which has been found in UK), a bronze fantasy cuirass, a weird animal pelt and the same problematic wooden scabbard:
Finally the temple... isn't really looking like a temple:
Honestly, you could use it for anything else and you wouldn't see the issue. There is nothing telling you it is a temple or any building with a religious function. This could be a storehouse, barracks, a noble house, a military camp etc.
The building isn't bad, except for the round shields, but it is super generic and unspecific.