Here's my modlist for my current cold world adventures in 1.20.4:
Terra Prety
Primitive Survival
Better Ruins
Sortable Storage
Self Recording Thermometer
Prospect Together
Less Wolfs and Bears
No Screenshot Message
Frozen Reeds (new)
At Waters Edge (new)
Not many mods aimed to remedy issues with a cold world, unfortunately, but on the plus side Less Wolfs and Bears and No Screenshot Message has great value for download energy spent.
I've added Frozen Reeds, which worked and spawned in reeds in places not discovered yet, so that saved a lot of storage trouble. I also added At Waters Edge for splitting and cultivating reeds, just in case.
I wish there was a flora pack for adding more bushes and so on to the colder lands, cause it is quite barren compared to temperate areas. I feel the transition from temperate to polar areas is a bit neglected in the game as of now.
Also a bit worried about whether flax will be found in a colder world. I've found heaps of rye, but no flax so far, and see it only grows in temperate areas according to the wiki.
For world generation I've ended up with the recommended values for Terra Prety, experimented with the landcover percentage between 30 and 50%, will probably end up at 40 or 50% at least.
Other values:
-102x102k world size with 50k polar-equator distance
- Minus 90% forestation (less trees)
-8x slower sapling growth speed (the waiting game)
-Cold and semi dry world (less thunderstorms, I hope)
-tool durability 125%
-temporal rifts off
-animals passive
-no class recipes
Peace and quiet and a bit chilly.