I agree with Debi on adding slowly, alot of these critters get added to tanks that don't have the food to support them yet. Assuming a tank that's had a chance to brew a while...
You are a little conch heavy, I would say one fighting conch would be enough, two tops. They need a chunk of open sand.
Yes, Scarlets are considered to be the most reef safe and my experience bears this out. I've never had the Hawaiin, I can't speak to those. Your numbers look good to me.
Cleaner shrimp like company, I would not buy just one.
I think you're a little weak on snails, I would add 5 - 10.
Just my 2 cents.