Thinking back I think I started with the Julii so I pretty soon discovered the pain for a newbie that is Patavium. Then I think it was Gaul and Egypt, then a few others I abandoned quite early. Then I thought it would be better to try the Greek Cities and entire world conquest to learn as much as I could ASAP. I used my experience of fighting units from all the other factions to decide whether they had potential.

1) What is the best Roman to start out with?

2) What are the top three choices in the following categories?

To maximise Denari.
To reduce rebel appearances.
Army structure.
Faction units.
Temples.
Mercenaries.
To stop units that run amok from doing so.
To cut devastation.