Iron Century Total War mod

So I decided to make a mod. I was trying a few times adding some more regions to vanilla map, but every time I would break tga files and ragequit for a half year, hence this time I decided to make my own map.

Map is humogously over the top borderline huge, but I make it for fun. (500x447)

Premis is that map for SSTW i distorted by mercator projection, and I make more globe like map less concerned about south and Africa and more on northern Europe and even Iceland.

I like early game warfare so I decided to start game in 936, a bookmark from Crusader Kings II, hence the name. I will draw a lot from CKII and mod for CKIII.

For factions I chose:

Islands (Hebrides, Orkaney)
Scotland
Wales
Ireland
England
West Frankia
East Frankia
Italy
Leon
Umayyads
Abbasids
Byzantium
Bulgaria
Hungarians
Czechia
Polans
Pomeranians
Balts
Danmark
Sweden
Norway
Suomi
Rus
Pechengs
Volga Bulgar
Khazars
Georgia
Venice
Pope

Gameplaywise I would like to stick mostly to vanilla and kingdoms, mostly for performence (i.e. huge mods like SSHIP or DAC are to slow for me). So:

Unit overhaul

Updating unit stats to current meta.

More religions

Judaism, Slavic, Tengri, Romuva, Suomensko, Norse.

Pagan conversion

Pagan factions, there would be 10 of them, could convert to Catholicism, Orthodoxy, Islam or Judaism with triggers. Like in Teutonic campain. If i would be able to, I will make triggers regarding war, trade relations, or princess marriage.

It will be trade off. Pagan factions will have cheaper and more numerous army, but could not advance beyond motte-and-bailey and town. Conversion will give them religion specific units like knights for catholicism, cataphrakts for orthodox or iqta for islam.

Non christian princesses

Every faction will have princess.

Region specific units

Some units would be accesable to all factions and will be region specific. For example Horse Archers on steppes or Viking Raiders in Sandinavia and northern British Isles.

Permanent forts

Like in Britannia campain. Hence map is huge, there will be a lot of them.

Emphasis on choke points on strat map

Map is humongous, but will be densely detailed with rivers, forests and mountains. Some regions will be almost impregnable due to natural borders, like Czechia, northern Italy or Georgia, other will be open, like steppes or or european plains. Permanent forts and castles will be placed in strategic places.

Emphasis on castles

Most regions will have castles and castles will be like in Teutonic campain. There will be no conversion between settlements. Cities will be placed in historically significant places, like London, Gdansk or Cordoba, civilised places, mostly Greece, Middle East and Italy, and densely populated places, so Netherlands and Rhine valley.

Holy Roman Empire

For both francian factions and Italy there will be decision to form Holy Roman Empire. I will see if this will mean new faction. If yes, then I will throw out Papacy.