Hello and welcome in Hell... Dorado
Concerning your question :
Are the starters for Westerners and the Saracens balanced enough for the first games?
yes, these two starters are balanced enought to play one against the other.
The two others starters well balanced are Demons and Losts. These play well together.
Concerning the 5th starter (Immortals) it is too powerfull (well used) to face these 4 first starters. Indeed, the Immortal starter is made to be able to face others factions that have more units that Immortals (which are prety young).
But begining by Immortals give a fine way to learn about their particular strategy
As Eusèbe said before, the 4 firsts starters are as well balanced to play together.
My preferance is :
Demons <-> Westerners
Losts <-> Saracens
But the main is to choose the faction you like
and last but not least : Have fun !
Alaster,