I have a question? I must be missing it, in the code above, how do you make subject of the email dynamic? Is it possible? Or does it have to be hard coded?
I have the Shinra template, so I hope you do too or it's the same. I assume you're making these changes in the contact.html page?
Did you also add your email address in the send-mail.php file? I am on my phone typing this so can't give specifics, but let me know if you don't figure it out from there.