I don't know wether this has been suggested before, but here goes.
In HOI1, you can promote your generals, making them able to command larger forces. How about assigning a new trait every time they get promotet (or maybe just a chance for attaining a new trait)? If possible, the trait would be determined from the fighting this person has been involved in, and succeeded in doing. For instance - in a given general has won a province with a fortress - he gets some unknown points as a fortress-buster. If he's been involved in leading armoured troops into battle - he gets points as panzer-leader and so on. Or the easy way - you randomly assigns a new trait to the person when promoted.
In HOI1, you can promote your generals, making them able to command larger forces. How about assigning a new trait every time they get promotet (or maybe just a chance for attaining a new trait)? If possible, the trait would be determined from the fighting this person has been involved in, and succeeded in doing. For instance - in a given general has won a province with a fortress - he gets some unknown points as a fortress-buster. If he's been involved in leading armoured troops into battle - he gets points as panzer-leader and so on. Or the easy way - you randomly assigns a new trait to the person when promoted.