Sorry for double posting, but I do really think this submod deserves a good deal of attention, but also because I wanted to raise a couple of issues I've discovered.
For whatever reason, all three counties in d_felwood start with all of their holdings without any upgrades. If build upgrades and wait for their castellan to succeed, it seems they always fail. I haven't experimented with giving them other kinds of buildings, but... now that I think about it, I'm wondering if it's a conflict with Flamequeen's building submod, but that wouldn't make much sense since it's only those three counties (c_felwood, c_amberly, c_galemont)
Edit: The same issue is occurring in Heart's Home. Normal building do build, just not the keep expansions.
Regarding House Hardyng, shouldn't they be moved further south, as they are sworn to House Waynewood? It's not clear whether they are closer to The Eyrie or the Sea (Ironoaks being the midway point), but they definitely shouldn't be up in The Bite.
Do you think House Caswell and c_bitterbridge should be moved out of d_blueburn and into d_roseroad? I've always gotten the impression that House Caswell is more important than the game gives them credit for; they're titled Defenders of the Fords, which would seem to imply that they would be sworn directly to High Garden rather than to House Meadows. I may be wrong.
Also, do you think c_inchfield should be moved closer to c_longtable, as both were held by House Merryweather for centuries? I would consider swapping it with c_smithyton, perhaps.
There also seems to be a bit of an imbalance with House Florent; the only other county in d_brightwater starts sworn to d_west_marches in every bookmark, and they are massively under powered compared to all of their neighbors.
Even though House Staunton now starts with d_rooksrest, every county in the duchy starts out independent in every bookmark except the conquest (that I've seen).
I would consider making the culture of the provinces in d_rosby, d_blackwater_rush, and d_kingsroad crownlander culture, and adjust the character history for that. I've adjusted the cultures myself, but not the character files yet. There are weird things currently like the Chytterings being riverlander even though they're surrounded by stormlander and crownlander cultures. Similar to House Mosborough.
c_mosborough is not sworn to the Rosbys in any bookmark even though they are now part of the duchy.
I would consider making Moat Cailin de jure part of Winterfell again as it seems the Starks love to hand the county over to Reeds currently. Not a huge deal.
Apologies for the long list of 'problems'...
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I really do love this submod! I hope you continue the great work!