- Crops, could be growing at a ( much ) slower rate , need extra stuff to grow properly, like, say, manure produced by domesticated animals and watering, either manually with a watering can or by digging channels where water would flow and water a radius of x squares ... otherwise crops should suffer heavy quantity losses . ( also birds or bugs could attack crops, and have measures of protection needed to be taken )
- domesticated animals don't even need water to survive. Food troughs should also be taking water . Another thing is protection from the sun, under trees or shelters. Stables for horses etc..
disease could be a thing too, saw that on another post. Also fights between them... Bulls do not tolerate other alfa males

- wild animals are almost all the same to hunt, with few exceptions I think. Boars, goats and Aurochs could be in packs, deer could run like hell from the beginning of the battle, foxes hide until you get very close, etc ( bring some wolves in, attacking everything in packs !! )
- Containers and vehicles are too easy to build, large stuff sould demand higher skill to construct, more materials like nails made out of nuggets, different kinds of glue and time for the glue to dry to be usable, make containers and vehicles themselves a tradable item in CF that way.
- Food, crops, meat, organic stuff in general could decay over time ( not wine or vinegar

More could come up if you guys agree.
I do not intend to suggest things to be impossible. I sincerely believe that it will be more interesting and rewarding to increase the complexity of some things like the above. Besides there are allways alternatives and more could be implemented to encourage cooperation, interaction and creativity.