That stuff with the passive factions in the end is amazing

. Didn't know this much money was possible to extract from them. Those nearly 200k you stacked up there in 20 turns are impressive!
One profit optimization opportunity you missed in the end though. You could have saved some money by taking the governor of Ereb Gobel out before constructing to avoid the building penalty. For further building cost optimization, it is valuable to get the wood resource early by taking Heorth (Fiefdom) or waiting till the Beornings have proceeded in Holt to a level that is close to tier 3 wood industry. Building it all up from scratch in an outland, as required in Thrimfeld, takes ages. Heorth will probably be the quickest since Dale should have it developed quite far until you get there and it is the only non-outland with wood for Rhovanion. Next to the direct effects of the building, Master Woodwrights will join governors quite regularly, give a further decrease to construction costs, and can be passed on to enjoy the effects elsewhere.