Hmm, tough call. Can't really say I've had any huge accomplishments. There are a few things I'm proud of though: Owning only WC polys, having two mokes (not really that big of an accomplishment but not many people do), never having any of my polys kill and eat another fish that I didn't mean for them to (although they have eaten already dead fish), and getting every single one of my polys to eat pellets on their first day in the aquarium.
As for things I'd like to do, it would be nice to have a tank of only dels, and to finally own a cong.