This script is still in it's alpha version, so I'm sure the member list and, indeed, the search system will be vastly improved. However, I don't think the filters are really needed as the current form of searching (the text box), as basic as it may be, functions perfectly. As for the additional options below a member's username, I know Kier said that he wants to make things very sleek and only available when you need it, so maybe he's thinking of adding it as a pop-up or a pop-down when you hover over the username. Anyway, I'm sure he'll find some intuitive way to implement this.
I think the member list should be revamped. It should display the search form and the blocks in the right sidebar by default, possibly in the expanded form.
The reason - no one is interested in looking at the winners of the weirdest user name contest - which is what both vB and XenForo display by default in the memberlist page. We even had the spammers sign up with a sole reason to get on the first page of the member list when it contained the members' home pages.