Going from B to C is a huge change. It was several years, I think, between releases, so I imagine there will be a huge adjustment period. In fact, I’d say it’s probably like playing an entirely different game.
Frozen items. Yes, indeed, frozen fluid is the bane of my existence. You can heat frozen foods and fluids up using a pot item. Vormithrax also just posted a video about how to defrost toilet water, which may interest you. In fact, I’d recommend you watch his tutorial series, since so much has changed and he makes excellent videos.
Aside from that, I don’t have much advice to give. Once you get used to it, the frozen thing just becomes an inconvenience rather than a game-shattering obstacle.
I can’t speak much to the other stuff, because I didn’t make the shift from B to C. There ARE a lot of zombies. Some of them are fast, some are extremely resilient. As you learn the new (I assume many of them are new for you) creatures, you’ll learn which to avoid and which can be easily bashed to death with little to no equipment.
If you’re really struggling, I’d advise you to adjust monster speed and monster resilience in the World Creation menu. When I was learning to play, I set everything to around 70% while I figured things out.
As for the game moving more towards realism – yeah, a lot of people take issue with that. I, personally, like it. That’s the development direction and I don’t expect it to change.
So, is the game harder? Probably. You’ve noticed the freezing and you probably noticed that first aid items don’t instantly heal you, anymore. But there are also many tools that didn’t exist in B. Like sprinting, for instance, which I believe was absent from that version. We also have crouching, now, if you’re playing the experimental.
I think if you go into it expecting it to be like the version you came from, you’ll probably be disappointed or even angry. Best to approach it like it’s a whole new game.
Also, welcome back to the apocalypse.