Don’t snowmobile over private property without permission. And if you don’t know the owners well, you may want to have written permission (and carry it with you). Sometimes property “managers” are not aware of what “owners” have done, and this will save time and grief, and maybe even an arrest.
Limit travel on public roadways, even where that is allowed. You’re harder for automobile drivers to see and hear (sometimes), and can be unexpected to see in the road at all. You will not likely survive a crash with an automobile at any kind of speed.
The frozen lakes thing is nice, but know that body of water. Any water with a current in it is likely to have thin ice on top. This can be caused by underwater springs, entry and exit points for rivers and streams, and “narrows” areas between adjacent ponds. There may even be property owners with “bubbler” systems along the lake, which retard or eliminate heavy ice formation around permanent structures such as piers and breakwaters.
Be extra careful while traveling at night.