Buildings:
New faction specific colonies (Rome, Carthage, Saba, Iberia, Thrace, Scythia)
All colonies (except Punic) have a levy type unit available to most factions other than their own.
New faction specific barracks (Carthage, Saba, Iberia, Thrace, Scythia)
Circle of Elders (academy-like building) (Gaul, Celts, Germania)
Third Level Farms (all with paved road present)
Foundry (all with iron present at huge city)
Huge cities have been restricted to certain provinces.
Paved roads, highways, and Higher level farms get a small law bonus now.
A garrison building that increases public order
The Amber Road, from the Baltic to the Adriatic.
With the Marian reforms the Barbarian factions gain many new buildings, and there is one other building all factions get.
Fourth level auxiliary barracks, with customary mercenary troops
Paved Roads (barbarians, except Scythia)
Pantheon level temples (barbarians)
Odeon (Thrace)
Hippodrome (Scythia)
Catapult Range (Scythia, this is changed from XGM)
Second level mines (Iberia, Gauls)
Foundry (with iron present at huge city)
Traits and ancillaries:
New triggers for Circle of Elders
New ancillaries and triggers for the garrison building tree
New trait "Loves 'Culture'" which forms a triad with the existing "Hates" and "Fears" traits.
Campaign:
New native culture buildings
New "Player's" Monument; it does nothing, but looks exactly like the AI monument.