Ideas

It would be so much nicer and easier to work with update events if we in the event got both the old and the new state of the entity updated.

Lets say you want to run some logic based on if the id of an entity has changed. Today there is no way, in the update event from the event broker, to determine what has actually changed. The only way I know how to handle such a situation is to do do the comparison in the validation rules.

Handling it in the validation rule is not ideal since you always needs to add the logic last in the validation to make sure that the entity will actually validate correctly before you execute any logic. And if the validation wouldn't go through you might need to manually rollback the changes you've made. Doing this in the actual event listener will ensure that the changes was actually valid before you do your logic.