The old overview page had a friend activity feed, so you could tell what your friends were playing and had done recently, and comment on new stacks and cheer them on as they made their way through games.

The front page and the profile page no longer have that. Would there be a way to put that back in?

The old activity feed you're referring to was beefed up into its own page, accessible with the My Feed menu item. It's a bit more powerful than the old one with the ability to save your filters, comment on items, etc.