1. Carthage = Spain (not Castille, Spain)
2. Numidians = France
3. Egypt = Burgundy
4. Spain = Habsburgs
5. Gaul = English
6. Germans = Danes
7. Dacia = Hungarians
8. Schythians = Poland-Lithuania
9. Thrace = Russia (Muscovy)
10. Greeks = Golden Horde
11. Pontus = Turks
12. Armenia = Moors
13. Parthians = Mamluks
14. Britons = Pope
15. Seleucids = Venice
16. Senate = Milano
17. Julii = Naples
18. Brutii = Teutonic Order
19. Scipii = ???


Note - this is not listed according to cultures

Where are the factions 20 and 21? I think you miscalculated! So all of this is really moot, since we only have one faction slot free, and most likely it will go to a second German faction. Although we could give it to Scotland, but imagine the whole area of HRE with only one faction (Habsburgs) and everything else rebels.
Even so we are ignoring such important factions like Tamerlane and his successors, various North African kingdoms, Qara and Aq Qoyunlu Turks (rivals to the Ottomans, major player in today's Iraq), Georgia, Moldavia and Wallachia, various Greek provinces, Sweden. And with only 1, perhaps two German factions... I can't believe you are seriously considering adding both Ireland and Scotland... Scotland perhaps, it's a trade off, but really no more.