Well I'll be straight to the subject.
Levelup - Give leveling a meaning and move the leveling gifts from Events to Achievements since leveling from 50 to 100 does not give you anything and is plain boring.
No Sleep - Same for the online time event. Add it to achievements and add 10 levels of playtime , 1 day, 3 days, 7 days, 9 days, 11 days, 15 days, 20 days, 25 days, 30 days and so on like that you'll increase players interest in staying online. *This could also give out a title something funny like "No Lifer" or "Not AFK All the Time"
Since there's such a huge difference between between spenders and non spenders I'd suggest some PVE Achievements.
Team Instance Achievements - Complete a certain team instance 10-30-50-100-200 times (Entrusting does not count)
Squad Instance Achievements - Complete a certain Squad instance 10-30-50-100-200 times
Normal/Elite Achievements - Loot a certain instance a certain amount of times
For god sake add few more Guild Achievements.
Hungry Buyer - Buy a certain amount of items from store
Hungry Buyer(Market Edition) - Buy a certain amount of items from guild market
A Helping Hand(Primary Edition) - Develop a certain amount of times with Gold
A Helping Hand(Intermediate Edition) - Develop a certain amount of times with 20 Diamonds
A Helping Hand(Advanced Edition) - Develop a certain amount of times with 200 Diamonds
A Helping Hand(Supreme Edition) - Develop a certain amount of times with 1000 Diamonds
Hungry for Power - Receive the Guild Offering a certain amount of times