Occultus and the hidden Factions (Discussion)

[Andronikos]

The culture wouldn't be problem, they would be Eastern Greek with few unique buildings at the beginning to represent Indian features, later (after Helenisation) they will use normal Eastern Greek buildings.
And there are many Indo-Greek units already ingame: I. light spermen, longbowmen, guild wariors, IH peltast, light hoplite, helenic hoplite (Saka reform), elite hoplite, Taxilans, Kambojas, IH cav. (Saka reform), Indo-Saka catas, 2 elephants
There are regular factions which have less units that would be considered their unique.

And the interests in India could be solved by some events, expenditure for out-of-map wars, few rebel stacks spawned randomly or something similar.

According to Wikipedia, Helenic rule in that region started around 200 BC and that would be that reform or dynasty change.