Running CentOS 6. I have postfix installed and it is sending e-mail. However, all my e-mails go to spam. rDNS & DNS setup. SPF for my domain also setup. Below are the e-mail headers.

Delivered-To: arowland@isl-edu.org
Received: by 10.216.184.134 with SMTP id s6csp1404129wem;
Tue, 9 Dec 2014 08:16:58 -0800 (PST)
X-Received: by 10.236.140.196 with SMTP id e44mr3691258yhj.19.1418141818368;
Tue, 09 Dec 2014 08:16:58 -0800 (PST)
Return-Path: root@mail.drewrowland.com
Received: from mail.drewrowland.com (io.puresimplicitydesigns.com. [104.236.45.134])
by mx.google.com with ESMTP id q8si1699536qco.8.2014.12.09.08.16.57
for arowland@isl-edu.org;
Tue, 09 Dec 2014 08:16:57 -0800 (PST)
Received-SPF: none (google.com: root@mail.drewrowland.com does not designate permitted sender hosts) client-ip=104.236.45.134;
Authentication-Results: mx.google.com;
spf=none (google.com: root@mail.drewrowland.com does not designate permitted sender hosts) smtp.mail=root@mail.drewrowland.com
Received: by mail.drewrowland.com (Postfix, from userid 0)
id 08165E0EC8; Tue, 9 Dec 2014 11:16:56 -0500 (EST)
Date: Tue, 09 Dec 2014 11:16:56 -0500
To: arowland@isl-edu.org
Subject: hey test
User-Agent: Heirloom mailx 12.4 7/29/08
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Message-Id: 20141209161656.08165E0EC8@mail.drewrowland.com
From: root@mail.drewrowland.com (root)

yup

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