Include product weight and dimensions

For the weight, you can just go in the config under the tab display and edit the front end CSS file and remove the code:
.hikashop_product_weight_main {
display: none;
}

For the dimensions, you will have to modify the file show of the view product via the menu Display->Views and add such code (that's an example for the length):
<?php if(isset($this->element->product_length) && bccomp($this->element->product_length,0,3)){ ?>
<span id="hikashop_product_length_main" class="hikashop_product_length_main">
<?php echo 'Length : '.$this->element->product_length.' '.JText::_($this->element->product_dimension_unit); ?><br />
</span>
<?php } ?>

We'll add an option for the dimensions yes.