I wouldn't put a Pearlscale in a 30, needs more room to live a long life

They need peaceful tankmates and room to swim [I'd go no less than a 75, and to me that's a little on the small size.]
Raccoons are a little bolder than most Butterflys, but they can be bullied by more aggressive fish.
My Raccoon would chase off my Dwarf Angels ..He is not at all scared of my Tangs either. He is ,however, intimidated by my Blueface . The Blueface is the only fish that will chase off the Raccoon.
I had the Raccoon in the tank before the Tangs and Blueface..I think order of introduction is key [usually] I had him with my Yellow Tang in the beginning and the Yellow messed with him too much, so they were separated.
If you added a Raccoon before the Purple Tang and Lion and let him get established, he should be fine..Not sure about the Grouper..IMO, It would need a bigger tank.
Remember, if you add the Raccoon..you'll never be able to have corals. That's my excuse for having two tanks
