There's not always the same number of provinces in a kingdom. This is often an excuse to avoid war. Perhaps a gains mod may make it more fair and hopefully encourage more war between different 'size' kingdoms.
(Size here means province numbers, not land or networth, smaller means fewer provinces, bigger means more provinces).
Suggested Metric: ( 1 - [smaller province number / bigger province number] ) / 2
If divided by 2, apply it only to the bigger kd hiting into smaller kd. My examples do it this way.
Otherwise, divide by 4 and apply both ways, reduced gains hitting down and increased gains hitting up.
(I'd love to see this tested on genesis next time it has larger kd sizes)
Example 1:
Kingdom A has 23 provinces. Kingdom B has 17 provinces
relative-roster-size metric: (17/23 = 0.739), (1 - 0.739 = 0.26), (0.26/2 = 0.13)
So, 13% reduced gains mod for the more numerous kd hitting into the less numerous kd.
alternatively, halve this to 6.5% and make it a boost for smaller kd and nerf for bigger kd
Example 2:
Kingdom A has 6 provinces. Kingdom B has 11 provinces
relative-roster-size metric: (1 - [6/11]) / 2 = 22.7%
Given nearly twice as many provinces I think a significant mod is great.
Other Common Examples:
18 v 22 --> 9%
21 v 23 --> 4%
19 v 20 --> 2.5%
24 v 25 --> 2%
Pros:
* People can still decide whether they think it is a fair fight, and just factor in this gains mod to their calculation.
* It allows smaller kingdoms and groups of friends to play against the big boys and just have more fun all round.
* The closer the kds are in number the smaller the modification, and for most normal kingdoms it becomes negligible. (eg 24 vs 25 is 2%)
Cons:
* Might need tweaking to avoid OP small-number-province kds.