Hey, palmer373! I just want to commend you for taking so much time and care over your stocking list. I think you're going to be really glad that you've put so much thought and research into your livestock.
That said, your proposed list does sound like an awful lot of fish for a 33G...also, if you're going to keep a mandarin, (a) I'd get one of the ORA ones coming out this summer that are captive-raised and trained to eat frozen and pellets, and (b) I wouldn't keep any wrasses--too much competition for food.
The yellow coris wrasses will eat featherdusters, baby brittle stars, and tiny shrimp. They also get big for a 33 (about 4"-5" long) and they need lots of room proportionate to their size, because they are
extremely active.
Pipefish are delicate and difficult to keep, especially with any competition for food. I don't know much about clingfish, but they sound like interesting little fish. Maybe check some books? Scott Michael's series on SW fishes is outstanding.
I haven't kept firefish, but they are beautiful and should do well in your setup (as long as you keep the tank covered). DD (I mention them a lot, don't I?

) has pairs of both the orange and the purple for sale regularly.
I don't know if your tank is open-top or not, but one thing to consider is that firefish and wrasses are notorious jumpers. Many fish will jump--I think my dottyback did, because I haven't seen her in a while (even after taking the tank apart to look for her).
Finally, if you want to keep the A. parvulus, you might want to make it a species tank, which IMO could be stunning. DD has groups of 5 available regularly; I think this tank size would be perfect for a little group of them. I haven't kept A. parvulus, but if they're like threadfins, which I do currently have (one of my favorite SW fish), they are very shy little creatures and on the delicate side until they're established. I also have to say that since the dottyback went AWOL, my threadfins seem more willing to come out into the open--she'd begun harassing them a bit. They definitely do best with very peaceful tankmates.