Id say to start with a orange digi or purple stylo, the are both pretty forgiving as SPS go and super cheep.
You wont need a chiller, Im running 2X radium B (20K) on a magnetic M80 ballest. Partly because of cost but mostly because they look better than any LED setup Ive seen. People complaining about halides heating the house and youge electrical bills, its more about the chiller than the halides. I spend more electricity heating my tank than lighting it with halides.
I didnt see what you are using for flow. I love cubes but they are kinda tricky that way. Also, love the light bracket.
Bonus points for ASM skimmer, Im running a euroreef.