To see recent posts, you can just click on "Posts" on the World page.

To see recent comments, you can click on "Comments".

To see comments directed at you, you can click on your inbox.

I added a Home page and a Feed concept, so you can add Boards and then see only the posts from those boards in your feed.

Of course, it is doable to have notifications, but it's another can of worms and I don't know if it is really necessary.