From what I understand (correct me if I'm wrong), the oldest surviving temples in Rome are the Temple of Hercules Victor (mid 2nd century BC) and Temple of Portunus (120-80 BC) built in the Forum Boarium of Rome.
It seems like most other temples were either started in the Principate period or were Republican-era temples that had to be rebuilt entirely after being destroyed in earthquakes and fires during the period of the Roman Empire. Either that or they're only fragments of temples and utter ruins. Take the poor Temple of Saturn for instance, which had to be rebuilt a few times and in the end is only a few pitiful pillars and a base for us to look at.
In either case I can see why you guys added so many of those rotunda-type temples in Greek and Roman cities. Plus the Portuna Temple above looks pretty much like the other standard style temple you see in the Roman settlements of EB II. Nice job, you guys! Being all faithful to the period and everything.