...I could do with some info on Indian religion at the time

D Blue, if you're out there?), AFAIK it was pretty much Hindu, though Buddhism was on the rise. What would be the most important temples of the area to represent in a scenario like this. ...
...Indian:
Great Stuppa (GW): +2

in every city, contiental mood effects.
The Ramayana (SP?)(SW): Greater chance of leader appearence.
Mandir: (Flavour temple, maybe req. temple, +3

?)
Stupa: (Another flavour temple. Maybe req. temple, +1

and 50% research?)...
Here's a start on images of the
Great Stupa (primary site of Buddha's relics) located at Sanchi. Stupas are all over the place and are the Buddhist equivalent of saints' tombs. Yoda Power made a
stupa (
not the Great One).
Many sites important to Buddhists are not temples; for example the
Deer Park at Sarnath, or
Nalanda University. One potential wonder would be the
Giant Buddhas of Bamyan that the Taliban destroyed. I've got links to lots of images of them.
Here's an old post of mine with line drawings of The Great Stupa, Temple of the Sun (a typical Hindu temple complex), and a classical era city gate.
Mandir is just the Indian name for a temple and is used of places built today as well as what we would think of as a classic temple architecture. Two sites with images and information on Hindu temples in general (
Wiki and
Templenet).
As to specific deities: There is the
trinity: Brahma usually doesn't get a temple of his own.
Shiva is the one with people putting ghee (clarified butter) and flowers on his
lingam, mandirs all over the place. The images you see of homeless saddhus meditating by the side of the road are often Saivites. Vishnu incarnates over and over, the most well known avatar being Krishna; lots of mandirs also. Also popularly worshiped: Ganesha, the elephant headed god, is well loved; he's associated with material abundance and intellectual knowledge. There are many important feminine deities as well, including
Kali and
Lakshmi.
One note: in Vedic culture (early to your time frame) ceremonies take precedence over places.
Let me know if you want more, and what to focus on.