Now all units are recruit-able in late tier buildings, so you can recruit all types of previously unlocked units.
also, almost-useless economy buildings "Markets, Ports, Merchant wharfs" are now enhanced to do what they Normally do in real life, aka Trading aka Real money! , as well as first tier roads produce a small amount of trade.
Let me know if you face any problems, or if you have any opinions related to it, Enjoy!
Note: Make SURE you BACK UP your "export_descr_buildings" in case something goes wrong.