To center the Username, title and rank, add this css to this h1 element:
HTML Code:
<h1 style="text-align:center;" class="blocksubhead prof_blocksubhead">
The edit pencil may off-center the username so you may need to move that up or somewhere.
To center the profile pic.
You'll need to add a new div around {vb:raw blocks.profile_picture} and center it like so:
HTML Code:
<div text-align:center;">{vb:raw blocks.profile_picture}</div>