be able to 5

[John]

Are these all OK and natural?

1-1. We can be good friends.
1-2. We will be able to be good friends.
1-3. We are able to be good friends.

2-1. I can't go to the conference.
2-2. I won't be able to go to the conference.
2-3. I'm not able to go to the conference.

Thanks.

[Rusty]

Are these all OK and natural?

1-1. We can be good friends.
1-2. We will be able to be good friends.
1-3. We are able to be good friends.

2-1. I can't go to the conference.
2-2. I won't be able to go to the conference.
2-3. I'm not able to go to the conference.

Thanks.
(All OK. However, I can't think of a time when I might use 1-2).