Timestamps need on topics
The forums does a terrible job at keeping track of when you last read a "category". Several times I've had the Portal Appeals category and its subcategories marked as read when I haven't read a single new post or clicked on the "Mark Category as Viewed". At least on the top level categories, I can use the timestamps to know when the last message was posted. However, this is not displayed on individual topics, so I don't know which topics have new posts since my last visit.