Please help with stocking my saltwater tank?!?!?

Heres the biggest thing you can do make sure that the sizes wont be conducive to one getting eatten. The triggers are the most aggressive most of the time but i see you have a lot of tangs listed too. Im not sure if the tangs will fight or not but you may want to look at that again. I can tell you that in a fish tank all bets are off. Its gonna be mostly your observations that will determine if it is working or not. I had a lionfish, bannanna wrasse(female), panther grouper, two eels(barred snowflake), foxface, blue hippo tang, numerous starfish and hermit crabs, and two bamboo cat sharks all living together at one time. After i had to sell them because my power company wouldnt turn on my power on a weekend... (bitter about that) the store owner was surprised tehy all got along. So just be watchful you may have to adjust it like i did (a puffer came and went after he started eating some friends :) no one died though). Try starting them off young and offer live food from time to time to lower the aggression.

EDIT ON THE TANGS: The tangs may work together the biggest problem with tangs is when same shaped tangs are housed close together 150 gallons might be ok. If you have similar shaped ones add them all at once and see what happens. Just be watchful aquariums make strange bed fellows.

You always add the most passive fish first. I would introduce the gramma first, pick any order for the tangs as long as the purple is last, and then introduce the triggers.

Triggers grow SLOW, so you should be fine with them. As you probably know, add the peaceful fish first... and avoid anything that can fit in your fishes' mouths (like the gramma). Also, 2 tangs could cause issues. Tangs should really be housed singly, but if you really insist, you have to put them in the tank at the same time... and be prepared to separate them if needed.

I personnally would be careful about the lion and the gramma .... they say you shouldn't put anything smaller in the tank that the lionfish could fit in its mouth. Cause chances are he'll eat it. I'd would stick with the tangs and triggers and not get anything smaller than them. Triggers and Lionfish get big very fast I'd even be wary about the clowns getting eaten. You may want to reconsider not having live rock as Lionfish are apparantly very messy. (We're starting a 150G aggressive tank also, hopefully soon.. I love lionfish) Anyway thought I'd throw in my thoughts on it. Good luck :)