The Holy Roman Emperor should be war leader when they are called in to defend the empire
I'm playing as Austria/Holy Roman Emperor right now. It is infuriating for France to declare war on a small nation within the empire, then I get called to defend them as their emperor, and yet the small nation remains the war leader. One of three things happen after I get called in and accept: 1) The war goes badly and the minor nation accepts a peace deal that gives France a bunch if not all of its territory; 2) The war is going alright, but then the minor nation white-peaces after a year or two; or 3) I am winnning the war, only to have the minor nation end the war demanding only a province or two + war reparations and some small amount of money. So many times have I been called into fight a war with France, I take up a huge amount of loans to afford a massive mercenary army to beat them, use up the HRE treasury to call in more members to help fight them off, only to have the war white-peaced right as I was starting to turn the tide. Then, just as I pay off that debt, the truces expire, France declares war again, and the process repeats.
It is not fun. They need to make the HRE the war leader automatically if they are called into defend the empire. Right now, the emperor is just forced to sacrifice their (and their allies') levies and money repeatedly with no real ability to inflict any damage/retake territory from France, because as soon as you start to win BOOM peace treaty. If the emperor had the option to choose when to end the war, they would make it much stronger and much less infuriating to play.