It annoys me how the wild boar can chase me across a whole map (if I don't just kill it, for some such reason as low level...) and never bothers to attack the passing orc. Sometimes they clash, yeah, but once I'm in sight, it's all mine!

I'd like them to be more like
'hunters': Take the easy targets.
'warriors': Take out those with most power, if known to them.
Or specific mission related targets.

Another thing:
Mana drain should cause actual drain on a monster mana pool (that might regenerate with time). So should spellcasting. It should be possible to empty an enemy's mana pool.
(And they could gain mana by draining you)

I mentioned a ban list for types of creatures you do not want to attack in a post. Another way of preventing undesirable attacks/talks (I have had problems with trying to go places where crowds force me to talk instead of walk) is to have a non-interaction toggle. With non-interaction, all mouse clicks would target the ground, with the purpose of walking. Regardless of what is there.