This isn't giving you "control" but it will provide you more space.
<p>nbsp;</p><p>nbsp;</p>
Two such as above gives a lot of space. One half of course.
Or, try this:
<font size="+3">
<p>nbsp;</p><p>nbsp;</p>
</font>
Vary the font size to provide different spacing.
Enter a "&" without the quote marks before the "nbsp;" in each case.