A simple way to boost player membership is as follows. New perm member benefit wizards who PVE can equip a second pet , stats can not overlap so if both have all damage talents the second pets all damage talents would have red slash through them as duplicate. PVE only and members only.
You would get a large boost in membership by doing this , since its PVE only pvp players cant boo hoo about people with double OP pets.
Another option for members only perhaps adding a 6&7th pet talent that can be activated when wizard has a membership. that can also boost memberships if a full second pet is too game breaking.
