In case this has gotten lost or forgotten over the years, some time ago we linked distance from capital penalty to apply equally to allies' capitals, so if you're conducting a war in support of a friend, you shouldn't have any problems with that particular nuisance.
(I recognize that there are other impediments to long-distance campaigns, and have Thoughts about how to address them, but as yet no solid Plans.)
First I hear of that. Good to know.
But what I'm yearning for is more the potential to sprawl across the map on Dwi, in a way where access to some strategic ports could very much create jealousy between realms, and conflict. Cities like Golden Farrow and Paisly are likely to interest a few parties. The handling of the north-west, which a few realms use differently, as well.
I don't want rogues gone, though, just looking at more options are we press onwards, and the ability to set up strongholds in remote location in an attempt to fight them everywhere.