Either/neither/any/none

Hello!
Could you please tell me whether these sentences are correct?

1. Both museums we visited were interesting (we visited 2 museums). Neither was expensive. Oh, I haven't been to either of these museums.

(We have been to plenty of museums):
2. All the museums we visited were interesting. None was expensive. Oh, I haven't been to any of these museums.

3. Tom, Angie! Can either of you play the piano?
4. Unfortunately, neither /neither of us can.

5. Tom, Angie, Kate! Can any of you play the piano?
6. Unfortunately, none/ none of us can.

For 2 things - both, neither, either
For more than 2 things - all, none, any

I would be grateful for your help.
Thank you in advance.