I try to visit here every month and be active during the Easter, Summer, Halloween, and December Holiday events. I pretty much only trade for my WL.
Currently, most of my WL includes the Internet Event, Butterfly Wolves/Bwolves, and other missed event outcomes. I try to keep my WL up to date so newer players can have a chance to trade with me. For anything Uncommon and below, I often don't mind trading older pets for newer ones, especially in larger quantities. I have more pets than I need, anyway.