The quick changes that can be modded that are new that I have seen in my quick glances:

Hording can be given to diffrent factions if units are avalible. Limited usefulness IMHO.

Setting up diffrent relationships between factions at start. This was in the RTW to some extent. But BI seems to take it further or it was always there but syntax and depth was unknown by most or all mod'ers.

The new loyalty system. Well some hate it some like it. The idea of having it for the time period does hit some at realism. But again the implementation was not that good IMHO.

Adding in new relgions and giving them to faction members. Not that big of a deal really other then the code factors. The changes in Vice and Virture files are mostly to deal with those issues. Code of course was changed to take into effect the conversions of each of these new traits. Again good for the time period but wouldn't add alot to earlier periods.

AI changes some of the changes are good and some of the same old behavior is there as well. It will atleast make an attempt to flank you now. Which is nice even if it half hearted or bungled. Then again it tries to do this all the time even when it is not a good idea. So you can plan for it and then beat him with the silly stick for doing it the 10000th time.

For those that are complaining about cavalry this was during the time of the rise of the horse. While they can seem to be a bit better then they should be and some of that is due to a few overzealous coders. For the most part alot of unit types that use to have a bonus to cav don't any more. So they die easy. And cavalry as I said was starting to take over the queen of the battle field role. Cavalry still die easy to any spear unit they try to charge head on if it gets the bonus.


Those are the majority of the changes I can see in the modding area.