1. Copper Banded Butterfly
2. Powder Blue Tang
The Copper Banded Butterfly will probably never happen. I've tried too many already, they just don't live.
The Powder Blue Tang I've had, but my 90g is too small and it was too agressive. So Unless I get my dream tank someday that is built into a wall in my custom built house, I'll probably never get another Powder Blue Tang, because I wont have a big enough tank..
But those are my 2 favorite!
90 Gallon Drilled Glass Tank w/ Corner Overflow: 492w (2x 150w 14,000K MH, 2x 96w Actinic CF) Coralife Aqualight Pro | Custom 34x15x15 Sump/Refugium | SWC Skimmer | Coralife Turbo-Twist 6x UV Sterilizer | Maxi-Jet Power Head w/Sure Flow Upgrade Kit | 120lbs of Live Rock | 100lbs of Live Sand