Let's simplify the world for a moment and imagine that there are two kinds of relationships; those that require small talk and those that do not. The former category covers most relationships. Big news requires a period of introduction and adjustment to develop a rapport with the person and after a time you can begin to talk about serious things. In the latter category that sometimes happens but isn't necessary. You can drop directly from "How are things?" to a discussion of the things that are most important to you without having to have a lot of introduction.
So when you only have two days in which to pack all of the visiting in that you possibly can and there's a whole bunch of other things going on, maybe think about people who are part of that second category and carve out space for them. You're close so it doesn't need to be two hours, but if you can find twenty minutes somewhere maybe the two of you can drop into that level of intimacy in conversation that you've built up over years of conversation.
And let's be honest. It's easier to find twenty minutes than two hours.