i have the same problem.. and i know that i can have costum, but if i like to change my avatar picture? is that possible?
Yep! it's possible to change your avatar picture o3o
It will cost 50 gold, though.
Do you see the flashing shopping cart
near your mini map at the top-right of your in game screen?
Click on that and the item mall
window will show up.
Then choose the 'Love' tab and you will see the Avatar Swaps in page 1 and page 2.
A screenshot for clarity: