As far as skimmers go...SPEND THE MONEY!!! Go with Euro-Reef as
minimum (you'd need the RS180)...ATI if you're feeling rich.
If you want Angels then obviously you aren't planning a reef setup. So I am confused as to why people would be suggesting you get a MH setup. Your choice of hanging some T5s over top wouldn't be the best idea because they come in 24" or 36". Power Compact fixtures come in 30". If I were you I would buy 2 dual (double bulbs) 30" fixtures, so you can place one towards the back of the tank, and one towards the front of the tank. They will penetrate 30" just fine for just fish. So I just saved you a bunch of money here to upgrade your skimmer.
Now if you ever thought of upgrading to a reef, you could maybe pull off a 250W HQI MH (mogul would never cut it), but you'd have to have good water clarity. Numerous T5s would also work with optimal water clarity. If you're just learning then I would suggest a 400W MH as they will easily penetrate the 30" depth.
There is NO WAY in heck you're gonna fit 130 lbs of live rock in that cube and have room for the fish to swim. With a FOWLR I don't see the need to put more than 70-80 lbs in there. So that just saved you more money to upgrade your skimmer!
BUT, I'd go with a traditionally shaped tank. Larger fish will be MUCH happier. With the cube you will be limited not by the gallons of your tank, but by the length of your tank. You would need to pick fish that are happy with a 30" tank, which means you're not gonna be able to put anything in there that gets bigger than about 4", OR anything that is a very active swimmer. That's a whole lotta little fishies in that big tank. PLUS, that cube is gonna look tiny compared to a 4' or 6' version.
I would suggest a 120 with measurements of 48" x 24" x 24". Then enjoy your Angels (not the huge species though). Or a 180 72x24x24...then you can get the biiiiig Angels!