I just downloaded 3.0r1 of the Picker and I think it's great. It's something that anyone developing the Settings panel for the Aquarium should aspire for.
The only thing that was not immediately intuitive was having 8 fish slots when Wide is unchecked at the bottom.
Other than that, it seems very nice and hope something similar will make its way into the Aquarium.
I am inclined to put a prominent link to your fish picker on the fan website.