Switch out the XR15 for XR30. If you checked out my sps RS170 that I linked above I found out that a single XR15 was not cutting it and had to double the light.
I am not saying that people are giving bad advice when they say to wait a year before adding SPS, I know Paletta wrote an article 6 months ago about how he couldn't keep acros in his new tank without adding real live rock first. If you look at my build thread (not updated in awhile, I know), I had SPS in there the day I added water to the tank and had Acropora in there during the first 3 or 4 days while using bleached dead rock. The tank is now 5 months old, still too new to grow Acros according the many folks, but I have a RS170 filled with colorful thriving Acropora coral.
I think that your biggest hurdle is being a "new hobbyist". While I pulled it off I have much more experience in testing and reading my tank than you do starting out. You can certainly do it and be successful with diligence, but there are certainly lots of learning experiences along the road.