Did you mention that blogger comment form have an ugly white empty space below it ?
this is due to the height of iframe of blogger commenting system , to remove this empty space find the following code (press control+F to open search box )
<a expr:href='data:post.commentFormIframeSrc' id='comment-editor-src'/>
If you can`t find this code just look for iframe or commentFormIframeSrc
The line that contain the code you found will be followed by a section like the following :
<a expr:href='data:post.commentFormIframeSrc' id='comment-editor-src'/>
<iframe allowtransparency='true' class='blogger-iframe-colorize blogger-comment-from-post' frameborder='0' height='410' id='comment-editor' name='comment-editor' src='' style='display: none' width='100%'/>
<b:else/>
<h4 id='comment-post-message'><data:postCommentMsg/></h4>
<p><data:blogCommentMessage/></p>
<data:blogTeamBlogMessage/>
<a expr:href='data:post.commentFormIframeSrc' id='comment-editor-src'/>
<iframe allowtransparency='true' class='blogger-iframe-colorize blogger-comment-from-post' frameborder='0' height='410' id='comment-editor' name='comment-editor' src='' width='100%'/>
change height from 410px (or any) to 260px (or any custom value that suits your blog)
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