well, liek you say it: they "should" remake Alexandros' empire. nah...
to need to choose wich way to go..as Macedon you coudl also choose to obliterate rome, not just staying focused on the East..

But seleucids shoudl destroy the ptolemoi. the baktrians need to capture a great part of the seleucids..

but dont make the conditions to specific, you just need to set the table: not scipt the history