What are the main things you want to see fixed from EB1 in EB2???

[ziegenpeter]

More flexibility for the player do recreate history (no being able to recruit lusitanian units outside iberia is a late campain disrupter, maybe some kind of slow colonial building that can recruit some of the more iconic factionals or "what if" reforms?)

I totally agree with that!
Or at least some more higher tier regional units, maybe with a very low replenish rate?

True, but for a lot of factions it would make sense. There are only a few factions where there are foreign rulers ruling a native population (Ptolemaioi, Seleukia and Pontus are the only ones I can think of right now).

I don't know. I guess if the occupant screws up, some macedonian noble offspring, who claims to be a ptolomaic descendant, can seize the moment?

With Seleukia and other descendents of Alexander's empire its more difficult because which regions should count as "core".

I'd say Anticheia, Seleukeia and perhaps a few other cities in syria.