Type of usage

Are the commas optional in these types of examples. Or do they imply different meanings with or without the commas. Would they be classed as vocative case and a natural pause.

Sorry, we don't have the information just yet.
Well, it's true statement. No ifs and buts about it. (should this be a comma instead of a period ?)
Now, I can see the point.
Now, it's just a question of time.