Yes, the ALX.exe is the only way to make it work. Because of the named problem with the governmental system it would not be wise to change completely to the merc pool and drop the MICs all together. An idea could be to move selected elite units that should be limited but are spammed by the AI, like Gaesatae, to the merc pool and assign them to the respective factions. Another idea could be to drop the regional MICs and move all these units to the merc pool, again assigned to their factions per region.