Fewer ships: We can't fight naval battles anyway, I don't think many people will mourn the merger of cogs, galleys and longboats. 20 slots can be reduced to 5-6.
Italian Men-at-Arms (mounted and dismounted): They're very similar to the normal MAAs that other factions use, except for +1 armor and slightly better availability. Could these 2 MAAs be combined, saving 2 slots? I think the increased availability of Italian MAAs can be preserved by modifying EDB entries?
Italian Cavalry Militia: Their 14 charge bonus looks good, but is absolutely useless in practice. I don't think their 14 charge bonus is realistic either; a bunch of rich folks in a militia shouldn't be able to form up for charges as devastating (as the number implies) as well-trained knights, and then be absolutely useless with a sword.
Polish Retainers: Same problem with Italian Cavalry Militia, they're good at charging but (slightly less) useless in a knife-fight. They're feudal status is also a bit weird because they're just a bunch of retainers instead of being part of the aristocracy.
Bodyguards: Can the number of bodyguards be reduced? The late bodyguards sometimes feel like a waste of space.
Mounted Sergeants: Should be available to all Catholic factions. For factions with local light cavalry units (instead of mounted sergeants), it's kinda depressing when you can't even build a single unit out of King's Stables when outside the AoR.
Chude Militia: For some reason, a “weak” militia unit has 4 armor.
Peasant Archers: Taking up 4 slots when they're virtually identical, except for armor upgrades. Same thing goes for peasants, spear militia, archer militia (England's archer militia is a bit too strong), crossbow militia (the Moorish crossbow militia has 4 armor??), peasant crossbowmen.
Longbowmen: I feel that the local longbowmen are way too strong, making England steamroll once they get access to these units. Reducing their ranged attack to 3 or 4, and their range to 170 (or less) would be better.
Yeoman Archers, Grandine Lancers, Lithuanian Regular Cavalry and other units with a 6-turn recruitment time: It's really long.....
Sherwood Archers: Fantasy unit. Interestingly, they have a shorter range than the other longbowmen.
Highland Archers: They're kinda useless, to be honest.
Pavise crossbowmen and their militia version: They're very similar, with slightly better stats on the professional version. I feel that they could be merged into 1 unit, probably militia quality. Same goes for the Genoese variants.
Free Company Longbowmen and MAAs: I would like to add "Free Company" to the unit names, to distinguish them from normal longbowmen/MAAs.
Javelinmen and their Lusitanian version: The Lusitanian version is slightly stronger, but fulfill very similar roles because they're both AoR units. At least Almughavars are unique to Aragon and available throughout the map.
Transylvanian Peasants: I feel like they're a fantasy unit with very limited availability.
Irish Kerns, Gwent Raiders, Welsh Spearmen and Longbowmen, Galloglaich: Too many special mercs in the British Isles.
Flagellants: (Relatively useless) Crusade unit with low availability, can probably remove with little effects.
Fyrd Spearmen: Very similar to spear militia (except for upkeep).
Pavise Spearmen: I'm not sure why such a generic-sounding unit is unique to Hungary.
Armored Swordsmen: Again, a very generic sounding unit that's unique to England, but also strangely a feudal unit. Almost identical to Scotland's Noble Swordsmen and the generic dismounted Chivalric Knights.
Battlefield Assassins, Hashishim (plus merc version): Fantasy units? Pretty useless too.
Turkish Horse Archers, Turkomans (x2), Turkopoles, Akinjis: Really similar, except some of them are merc units with higher upkeep (and/or reduced numbers).
Siphais (Fari Cav), Mamluk Archers: They have an absurdly long range. The same goes for Bekh Druzhina but the latter doesn't feel so absurd.
Moorish spearmen (Spear Militia, Arab Infantry, Nubian Spearmen, Lamtuna Spearmen, Heavy Spearmen): The Moors have too many pointless varieties of spearmen, and a bunch of semi-redundant swordsmen too.
Tabardariyya: Their availability, along with the Mamluks, should be reduced somewhat. Late game Fatmids just spam endless waves of these units.
Mongol archers: Mounted Khorchis are weaker then Nukeri, when the description says they’re the elite within the elite. Then, Dismounted Khorchis are weaker than the Merguen, which are the elite units within the elites of the elite? These Mongols use too many superlatives. Additionally, why doesn’t the Merguen have a mounted version?
Dismounted Turhagut: There’s 2 entries, one of which is misspelled.
Artillery units: Apart from merc siege units, there are also duplicate artillery units like NE Ballistas, ME Ballistas etc.
Halberd MAAs and Halberdiers: The Halberdier is somewhat like the late version of the Halberd MAA, and recruited as a late professional instead. They’re really similar for the most part. I think it wouldn’t be a huge concern if these units were merged.
Genoese Carroccio Standard: The voice actor actually says “Standard of Milan” instead of Genoa.
Smolensk Infantry, Desert Raiders: I don’t recall seeing these units in the game.
Light Swordsmen and MAAs: Aren’t these units the same thing?
Andalusian Infantry: Very low availability, barely seen unless fighting the Moors for a hundred turns.
Normal Serjeants: Almost identical to Spearmen Sergeants.
The incredibly bloated roster of the Crusader States: They have a ton of useless unique units in the game: Knights of Jerusalem (x2), Knights of Lazarus (x2), Constable of Jerusalem, Canons of the Holy Sepulcher, Edessan Guard, Syrian Auxiliaries, Marinae, Templar Sergeants, Squires, Heavy Spearmen, Zweihander, Guard, Crossbowmen, Longbowmen, Confrere Knights. That’s 18 unique units for a faction that’s almost always wiped out by the Fatmids. Their roster could be trimmed extensively, using other preexisting units. For example, Canons of the Holy Sepulcher can be removed, the Knights of Lazarus can be replaced with Knights Hospitaller (they’re technically from the same order), the Templar Heavy Spearmen and Zweihanders can be replaced by Templar Foot Knights, Templar Confrere Knights can be replaced by Knights Templar, Templar Crossbowmen/Longbowmen can be replaced by some generic crossbow/longbow unit, Syrian Auxillaries can be more numerous (currently they’re virtually nonexistent). Keep the Templar Guard because they’re so cool (although they’re more suitable candidates to be replaced). This will free up a ton of slots to expand the rosters of other factions.
The Lithuanian roster: Also quite bloated, but feels unique instead of pointless like the CS roster. However, a few units could be streamlined: Lettish crossbowmen (kinda generic), Lithuanian and Ruthenian archers (overlapping), Baltic and Ducal spearmen (somewhat overlapping), Ducal Cavalry (useless and expensive), Lithuanian Cavalry Militia (generic too).