http://community.elgg.org/plugins/854839/1.0/pagehandler-hijack-18x

I created this plugin just for that purpose, though it only translates the first part (the actual page handler).  In order to translate the 'all' portion you'd have to actually edit the plugins themselves en mass.  Note that the pagehandler hijack does have an outstanding bug that makes it incompatible with certain plugins that also use the 'route', <handler> system - but otherwise it works ok.

No. Your best bet is to keep up with Elgg upgrades. The 1.8 series has had several reductions in queries per page and there are more on the way.

elgg_get_site_url() is not going to give any improvement in performance. 

Look at index.php of mod/custom_index/

This is how I did it

<div class="index_box">

<?php $newest_members = elgg_get_entities_from_metadata(array('metadata_names' => 'icontime', 'types' => 'user', 'limit' => 15));

 ?>

            <h2><?php echo elgg_echo("custom:members"); ?></h2>

            <div class="contentWrapper">

            <?php 

                if(isset($newest_members)) {

                    //display member avatars

                    foreach($newest_members as $members){

                        echo "<div align=\"center\" class=\"index_members\">";

                        echo elgg_view("profile/icon",array('entity' => $members, 'size' => 'small'));

                        echo "</div>";

                    }

                }

            ?>

       <div class="clearfloat"></div>

       </div>

        </div> 

Especially, it would be interesting to know if this bug still occurs on Elgg 1.8.19 as there were some bugs fixed in the blog plugin in the meantime.

I just tested on Elgg 1.9 and it doesn't show the drafted blogs either, it's likely this bug still occurs in v1.8.19.

I can take a look at it again to make sure. If still happening, I can submit in the fixes.

Confirmed. I opened an issue at github: https://github.com/Elgg/Elgg/issues/6682.