Try disabling the AutoP plugin,
or encapsulating the <br /> tags within a div like:

<div>
<br />
<br />
</div>

Or a few empty paragraphs. like:

<p>
</p>
<p>
</p>

Or you could add something like this:

		b2evoButtons[b2evoButtons.length] = new b2evoButton(
				'b2evo_sep'
				,'SEP', ''
				,'<div class="sep"></div>',''
				,'s'
				,'<?php echo T_('Add a vertical SEParator between items') ?>'
			);

to your _quicktags.plugin.php file, which will add a button in your editor to insert a DIV with a class of "sep".

Then add something like this to your stylesheet:

.sep {clear:both;margin-bottom:30px;}

Adjust the margin to how much of a space you actually want. Depending on your specific blog style and how you tend to structure your posts, you might find that using a "height" works better than using a "margin"

Anyway, this method will ensure that your whitespace is always uniform wherever you use it.

jj.

The only thing I would add to jibberjab's "button" suggestion is that the sep div should include an "&nbsp;" to prevent having empty div or p tags.

If you don't want to add a hack to the quicktags plugin you could just add the new .sep to your CSS and where you want a large break simply include

<p class="sep">&nbsp;</p>