Boost: I want other people to see this post.
Like/Favourite: I want the author to know that I value this post.
Bookmark: I want to remember / see follow ups to this post.
Unfollow: I don't want to see this person's posts unless someone else boosts them, or they mention to me.
Mute: I don't want to see this person's posts (temporarily or otherwise).
Block: I don't want that person to interact with my posts, or to see theirs.