I like to see what skills and cool stuff people can come up with. I was thinking along the same line as the armor, however, I was going with different custom hair... I also think unique original headgear is nice to see as well. Whether modified or all custom.
A little side thought, maybe a big far fetched thought, is as the first place prize in the custom helmet, hair, or armor as voted on or chosen by BF, is the eventual introduction/product of your item. This I'm sure would be a big prize and take time to achieve the exact version for final product, and time of the artist and BF to get accomplished.
The next idea is nothing new but the old shield design contest was great. This time around it could include all the shield made by BF.
Lastly, and again not a mold breaker, making your own faction. It could be a castle faction, space group, explorer team, or an organization that has a look or design making it its own. Like the crownies, agents, rockraiders and so on.
I like these ideas. Welcome to the forums Schvatts.