These advises are a little outdated with phpBB3 and our SEO tricks. Take a look at the demo server : http://phpbb3.phpbb-seo.net/
The view latest post has become a text link using the topic url instead of the original post url, what was wrong is now good to keep.
For usernames, it's another debate, I personally think that profile can be indexed if your forum has enough topics, once adding the profile would not create a too big proportion of page with few content.
By default, profile are only available to registered users on phpBB3, and bots do not see user profiles links.
Indeed it looks like you are using SMF, with some issue with stylesheet apparently, I cannot see any style applied to the forum right now.