I personally use a refractometer. Much more accurate.
Stocking list is good, you could add a small schooling fish like chromis, or a firefish, a blenny. Some others like that.
I personally would get more rock. I have 60 pounds in my 40 breeder.
I used pool filter sand. Love it. Perfect consistency.
As far as the lights. Are you wanting corals? Go with a four bulb. FOWLR
? 2 bulb will suffice.
I have a 4 bulb with 2 daylight, and 2 actinic for future corals.
Sounds great so far though!