The map is a little tight in the early stages of the
game.  Everone benefits from agriculture.

Since there are no floodplains there each river
valley is a flood zone.  Because some of the flood
zones are small, the rule is that a flood destroys ALL
units in the flood zone, unless you have engineering,
in which case it destroys HALF (round down) of your
units there.

Use of the AST is the same for the nations involved,
though the Illyrians can call themselves the
"Macedonians" or "Dorians" if they like.  I think
Thrace is the trickiest one to play.  Like Crete, you
need boats, but building them too early will cost you.