Yeah, general rule of thumb here: Use your tank thread to document your tank and engage with people who reply to it directly, especially on topics of narrow interest (for example, in my tank thread, I often bemoan the state of the hobby with other locals). If you have general questions, use this forum or one of the subforums dedicated to more narrow interests (but still broad enough to see traffic).
With regards to stocking your tank: Overall looks good. I personally would skip on the melanarus. They don't harass corals, but they will go after mobile invertebrates, especially anything with legs. Mine has cleared out any and all shrimp and crabs that have gone into my tank. They are good about picking off pests (especially flatworms) but there are other fish that will do the same job without attacking crustaceans. If you're wanting to pick it up for that purpose, I think your pink-streaked wrasse is already doing that for you. You can also bring in a few Springeri (sapphire) damsels to do the same job. Melanarus do look very striking, but I won't be replacing mine when it shuffles off this mortal coil.
For tangs, almost anything in the bristletooth genus (Ctenochaetus) will work. Tomini are popular, as are the yellow-eye koles. But really, anything in that genus is good. White-tail is nice if you don't mind spending for it. Tomini, white-tail, yellow-eye kole, blue-eye, bluelip, two-spot... Quite a few options, and most of them good for a 4' tank.