have you looked on this site for min tank sizes for the different fish? we are also looking at stocking a 33g tank and didnt see any butterfly fish that could handle anything less than 50g.
have you looked at the dwarf angels? lemonpeel, flame, bicolour, coral beauty, half black angels all will fit your tank, are somewhat butterfly looking. flame hawkfish/longnose hawkfish, some of the reef safe wrasses, or twinspot hogfish are a few others that get into the 4 - 5 inch range and are supposedly alright in a 33g.
hahah, do what we did, hop on these websites and go through the fish group by group and read up on requirements and compatability. for our sized tank there is only so much you can do but with a little research you can make something pretty cool methinks.
i dont necessarily know how great these shops are (j&l are great) but its a start in finding info:
this site
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