As romani I never seem to have money problems starting out, I like to maintain my 2 starting legions and other garrisons and the fleet 2. I just raise taxes and capture taras and rhegion. Main problems seem to occur with smaller, or landlocked factions.

I've finally got an economy section in the WIP manual, might check it out, I could always use some feedback as well. Public comments should be enabled on the wiki:

http://ebmanual.wikispaces.com/Economy