Making a Killer wp_link_pages

Your pagination links are wrapped in with this tag <p class="pagelinks"> so giving them all the same spacing is easy using CSS like so:

.pagelinks a { margin: 0 5px !important; } /* override other defined margins */

maybe you want them all centered on the page too:

.pagelinks { display:block; text-align:center; }

making the current page number a link to the top of the page – try this in before/after your previous page & next page if statements:

if($page == $pagenow) { // check if current link is current page
    $args['pagelink'] = '<a href="#header">%</a>'; // assuming top div has ID "header"
    } else {
    $args['pagelink'] = '%';
    }