1. The English already had a history of cavalry usage before the Normans arrived. At least one source says Harold Godwinson used cavalry at the Battle of Stamford bridge, and the Fyrd was a mounted mobile response force. For the Norse, they really should only have light cavalry at most, I didn't add anything for them here that wasn't in the base game. Same with Artillery, it was already in the base game and I designed this as a sort of DLC that expands to a later period.

2. If left to their own devices it seems to be 50/50 without player interference if the Normans live or die. Another stack actually makes them do worse initially in my own testing, as their economy can't support it. Sadly my scripting skills are garbage or I'd likely have a better solution here. I've found in my own campaigns that slow and steady expansion is key. But you tend to bog down around the Thames. As a hisotorical note, William also had trouble pacifying the north and constant small rebellions.

3. I think there's already a mod for that? So long as it doesn't change the startpos it should be compatible.

yep, found that mod. i cant really understand why were the governors capped by CA to begin with. thanks for taking your time to respond. best of luck;)