Add more map "features" (like Cold Zones and Rivers), for fun and variety

It'd be nice if some maps had Cold Zones, while other maps were 100% Cold Zones (pure arctic maps, a "challenge" map type), with this having consequences:
For instance, Housing would require an input of heat, maybe in the form of Steam-Lo or Steam-Depleted, or you could use any kind of Steam in a new Heat Exchanger structure to impart thermal energy into Water, so it becomes Hot Water.
Likewise a few Buildings would function poorly if placed in a Cold Zone, and others not function at all. This would include Farms, so maps that are 100% Cold Zones need some other food option. Maybe ocean/river fishing, or advanced indoors hydroponics?
There could also be Hot zones, and 100% Hot Maps, where Housing requires Air Conditioning, but Solar works a lot better.
And then Rivers, serving both as logistical hurdles (needing Bridges or Ferries), as sources of Water (and fish), and for hydropower (Mechanical Energy, which you then Shaft into Turbines).Rivers would enrich the game a lot!

Note, I'm not saying that Farms should necessarily stop functioning completely, but I do think non-Greenhouse Farms should have a marked reduction in productivity, like -67% or -75%, and with Greenhouses being hit less hard at maybe -50% or -40%. The whole idea is to have it be fuctionallity different to play in a Cold Map as opposed to on a Normal Map, and with some other maps having mostly normal zones but a few cold zones where you can still do some kinds of industry (those that aren't hit by the cold) but you wouldn't want your people living there), simply for the sake of gameplay variety and also visual variety.

100% Cold Maps also, as suggested earlier, creates a call for the addition of non-Farming based Food sources, such as fishing, which I know that others have asked about.
I'm not quite sure how to "industrify" the catching and processing of fish, so that it adds fun choices and options to the game, but perhaps the Weather system can be expanded to also sometimes have Stormy Weather that makes it dangerous for oceanic fishing boats. The player can then be given a toggle to choose whether or not they should sail out during Storms, i.e. risk vs reward.
Another possibility is River-based aquaculture, like "farmed salmon" or whatever. Or initially there could be Seafood (both in Rivers and along the oceanic coastlines) that can be harvested but which doesn't renew, stuff like oysters/mussels that have accumulated over millenia, or forest animals that can be hunted but will go extinct quickly (like in Age of Empires 2 where you first gather berries and hunt deer, then switch to Farming)