Thank you very much for your advise. I think that I will just give the Indian territories to AS and give them some repite afterwards. They are pretty much doomed right now elsewhere
Spoiler Alert, click show to read: 
(they have three territories in Asia Minor, three more in Mezopotamia, Persis+Karmania, and Sogdia+that one around Alexandria Eschate - all others taken by Pahlava and PONTOS - amazing AI expansion so far, I will post the picture in the AI expansion thread soon).
so before I manage to conquer India and find a plausible reason for the spilt of my Kigdom, this might well become their last stronghold.

Anyway, thank you - Centurio Nixalsverdrus, MarcusAureliusAntoninus and Lysimachos - once more and if anybody has any new ideas, I will welcome these as well.