Is it already present, or does this constitute extension request?
There are some graphics such as airships that are useless for any other purposes but it would be nice to see them only until ~1940...
Since movingobj are only made during map creation, it does not really matter, or?
I didn't know they are "fixed". If they had some sort of timeline, you could use them for many other eye candies - public ships, planes,... not just timeless animals!