Thanks for the data! Heres what it turned out.
Of course this is only one test so it might not be representative of the patch, but it does look like we are a bit under what "seems to feel right". Using 1.5.6 as a guide I think a good spot to be in is when you have 30% or less wars that are shorter than a season (orange, red and grey on the chart). You can see on 1.5.11 we are at about 40%.
I also wanted to point out the kingdom win % and how that has changed over the patches, I think its a great sign for overall balance.
I really like what i see in 1.5.11, to me good balance here is having everyone between 25% - 75%, so there are still clear winners but no one that is guaranteed to always win. It's great to see Khuzait come down from almost 100% to around 60% and to not see anyone below 30%.
Just so people understand if you did do this, war lengths would increase to the levels seen in 1.5.0. Where wars are multi year events. Back then snowballing was a major issue and long wars attributed to it, maybe now that snowballing has been fixed we can test out longer wars.