Optimizations may not be the most fun thing to work on (or read about!), but as a game gets bigger it becomes more and more important. I've been putting off optimizing the load times but after getting feedback from players with medium to large sized towns that the load times were approaching one minute, I figured it was time to do some of that work.
The major cause of the load times in HammerHelm is due to the terrain changes that each building requires. When the game loads a building, it has to remove the grass from under the building and paint the roads on the terrain in front of the building. Updating the terrain can take a while. The biggest optimization was having one object control all of the terrain updates rather than each individual building.
Picking up and moving a building could also take a long time after placing the building in its new spot it due to similar terrain updates as the load times. For a large town, this could freeze the game for over 12 seconds. That's way too long.
So I spent some time optimizing both of these and using a 55 structure town the load time went from 47 seconds to 12 seconds and moving and placing a building went from 12 seconds to about 1 second!
After recording this video, I did some more optimizations and got the load time to about 10 seconds!