Oh my. That's a lot - not sure about the necessity of all of them, but there is a couple of good ideas.
1. AFAIK "root cellar" is essentially the same as "earth cellar" (the former is a more american term, the latter is more british). I don't feel we need a specialized building for just storing fruits/tubers/etc. - I think a cellar like this, that takes just a little space overground but lets you create stacks of them inside (as a regular cellar does) would work quite fine. As for ice house - personally I think a better idea would be to actually (severely) reduce snow decay in cellars (either building cellars or earth/root cellars).
2. The idea of a stillroom I'd rather see as a constructable object inside buildings - potentially immovable, similar to the milling machine. But the idea is not bad. Same for slaughterhouse - I think a buildable "meat rack" in whatever building you like might work better - similar functionality, more flexibility.
3. I just learned a new word today - "byre"
- I like the idea, but it would probably be a bit too complex to be worth implementing.
The rest... I have no strong opinion to be honest. But they sound like possibly interesting ideas.