I am hoping 1.12 has some coalition improvements.
1. Namely I feel Rivals should not be able to join a coalition as a full member.
Rivals should be able to "support" a coalition defensively as isn't that their point? Not join a coalition and offensively bend them to its will because it is losing to it's RIVAL. Isn't that the point of a rival? Someone of similar size/strength?
I find it extremely disappointing when I have 2 rivals that are in 1 coalition and I have to keep beating them both down over and over AND they keep declaring offensively!!!
2. Perhaps make Rivals declare their OWN war alongside a coalition war if they want to declare offensively?
3. Junior partners (AI) should be able to peace out when they are fully occupied AND have a specific war exhaustion. Currently some larger nations sometimes peace out, but others don't at all. There is definitely some additional checks to peace out that should be being made.
4. AE from a rival should be reduced, as again, it is a rival. Perhaps only if it is an enemy? (rivals you?). This would make AI/Players have to choose their rivals more carefully. It would also make it less "gamey" since you couldn't just rival someone weaker and beat them down, they would have to "choose" to rival you back.
This would also allow a change perhaps to full coalition members to be able to defend anyone against offensive wars started by the target, but would be off set by the other nerfs, as this would make them more effective at stopping your overall aggression.
On top of this, coalitions could also have a separate peace deal option from white peace, extending the duration, can be done with junior partners to lengthen the truce period, and perhaps put an extended coaltion duration.
I would also like to see the threatend status expanded. Such that if someone is threatened but "loyal" they treat you mostly as they do now, but if they are threatened but upset they will join a coalition as a defensive member? I personally think the threatened status needs a "loyal" status, because if you did never did anything to directly upset an ally, just outgrow him, they shouldn't naturally be threatened and "upset", but instead threatened and loyal.